Daily Archives: March 18, 2011

US military spy operation manipulates social media with “sock puppets” to spread propaganda and disinformation

Gen David Petraeus has previously said US online psychological operations are aimed at ‘countering extremist ideology and propaganda’. Photograph: Cliff Owen/AP

Military’s ‘sock puppet’ software creates fake online identities to spread pro-American propaganda

guardian.co.uk | Mar 17, 2011

by Nick Fielding and Ian Cobain

The US military is developing software that will let it secretly manipulate social media sites such as Facebook and Twitter by using fake online personas to influence internet conversations and spread pro-American propaganda.

A Californian corporation has been awarded a contract with United States Central Command (Centcom), which oversees US armed operations in the Middle East and Central Asia, to develop what is described as an “online persona management service” that will allow one US serviceman or woman to control up to 10 separate identities based all over the world.

The project has been likened by web experts to China’s attempts to control and restrict free speech on the internet. Critics are likely to complain that it will allow the US military to create a false consensus in online conversations, crowd out unwelcome opinions and smother commentaries or reports that do not correspond with its own objectives.

The discovery that the US military is developing false online personalities – known to users of social media as “sock puppets” – could also encourage other governments, private companies and non-government organisations to do the same.

The Centcom contract stipulates that each fake online persona must have a convincing background, history and supporting details, and that up to 50 US-based controllers should be able to operate false identities from their workstations “without fear of being discovered by sophisticated adversaries”.

Centcom spokesman Commander Bill Speaks said: “The technology supports classified blogging activities on foreign-language websites to enable Centcom to counter violent extremist and enemy propaganda outside the US.”

He said none of the interventions would be in English, as it would be unlawful to “address US audiences” with such technology, and any English-language use of social media by Centcom was always clearly attributed. The languages in which the interventions are conducted include Arabic, Farsi, Urdu and Pashto.

Once developed, the software could allow US service personnel, working around the clock in one location, to respond to emerging online conversations with any number of co-ordinated Facebook messages, blogposts, tweets, retweets, chatroom posts and other interventions. Details of the contract suggest this location would be MacDill air force base near Tampa, Florida, home of US Special Operations Command.

Centcom’s contract requires for each controller the provision of one “virtual private server” located in the United States and others appearing to be outside the US to give the impression the fake personas are real people located in different parts of the world.

It also calls for “traffic mixing”, blending the persona controllers’ internet usage with the usage of people outside Centcom in a manner that must offer “excellent cover and powerful deniability”.

The multiple persona contract is thought to have been awarded as part of a programme called Operation Earnest Voice (OEV), which was first developed in Iraq as a psychological warfare weapon against the online presence of al-Qaida supporters and others ranged against coalition forces. Since then, OEV is reported to have expanded into a $200m programme and is thought to have been used against jihadists across Pakistan, Afghanistan and the Middle East.

OEV is seen by senior US commanders as a vital counter-terrorism and counter-radicalisation programme. In evidence to the US Senate’s armed services committee last year, General David Petraeus, then commander of Centcom, described the operation as an effort to “counter extremist ideology and propaganda and to ensure that credible voices in the region are heard”. He said the US military’s objective was to be “first with the truth”.

This month Petraeus’s successor, General James Mattis, told the same committee that OEV “supports all activities associated with degrading the enemy narrative, including web engagement and web-based product distribution capabilities”.

Centcom confirmed that the $2.76m contract was awarded to Ntrepid, a newly formed corporation registered in Los Angeles. It would not disclose whether the multiple persona project is already in operation or discuss any related contracts.

Nobody was available for comment at Ntrepid.

In his evidence to the Senate committee, Gen Mattis said: “OEV seeks to disrupt recruitment and training of suicide bombers; deny safe havens for our adversaries; and counter extremist ideology and propaganda.” He added that Centcom was working with “our coalition partners” to develop new techniques and tactics the US could use “to counter the adversary in the cyber domain”.

According to a report by the inspector general of the US defence department in Iraq, OEV was managed by the multinational forces rather than Centcom.

Asked whether any UK military personnel had been involved in OEV, Britain’s Ministry of Defence said it could find “no evidence”. The MoD refused to say whether it had been involved in the development of persona management programmes, saying: “We don’t comment on cyber capability.”

OEV was discussed last year at a gathering of electronic warfare specialists in Washington DC, where a senior Centcom officer told delegates that its purpose was to “communicate critical messages and to counter the propaganda of our adversaries”.

Persona management by the US military would face legal challenges if it were turned against citizens of the US, where a number of people engaged in sock puppetry have faced prosecution.

Last year a New York lawyer who impersonated a scholar was sentenced to jail after being convicted of “criminal impersonation” and identity theft.

It is unclear whether a persona management programme would contravene UK law. Legal experts say it could fall foul of the Forgery and Counterfeiting Act 1981, which states that “a person is guilty of forgery if he makes a false instrument, with the intention that he or another shall use it to induce somebody to accept it as genuine, and by reason of so accepting it to do or not to do some act to his own or any other person’s prejudice”. However, this would apply only if a website or social network could be shown to have suffered “prejudice” as a result.

As crises unfold around him, Obama seems curiously unengaged

Globe and Mail | Mar 17, 2011


No one begrudges a President his sports fixes. But Barack Obama’s decision to unveil his college basketball picks on ESPN while crises unfurled in Japan, Libya and Bahrain sure made a mockery of the “fierce urgency of now.”

As he jets off on a Latin American junket leaving it to Democrats and Republicans in Congress to duke it out over budget cuts, Mr. Obama has left more than a few wondering whether he has become a “spectator president.”

When upper-case headlines become the daily rule, you know you are living in exceptional times. But from the disaster in Japan to the rebellion in the Middle East, the most powerful man in the world seems oddly uninvolved.

As Congress lurches from budget deadline to budget deadline – funding government operations for only three weeks as it fights over the size of spending cuts for the rest of the fiscal year – the President has stood to the side with his arms folded.

This can’t be what he had in mind when, channelling Martin Luther King during his presidential run, he made the “fierce urgency of now” a leitmotif of his campaign. So, what gives?

No one, probably not even the folks at Fox News who accuse him of being AWOL, honestly believes that the brainiac President is disengaged. But as Americans learned during the Gulf of Mexico oil spill, public displays of empathy and outrage are not his bag.

The rest of the world is now discovering this side of Mr. Obama. His comments on the unfolding drama in Japan have been cold and statesmanlike. “It is a crisis in Japan. It is not a crisis in the United States,” his press secretary retorted when asked whether a looming nuclear disaster warranted postponing Mr. Obama’s trip to Brazil, Chile and El Salvador.

The extreme caution with which the President has reacted to the unrest in the Middle East, backing a no-fly zone over Libya only after Moammar Gadhafi’s military was advancing on the last of the rebel forces, has disappointed even his political friends, including Senator John Kerry.

His unwillingness to enter the fray over the budget deficit, arguably the greatest threat to America’s national security, has led members of his own party to throw up their hands in exasperation.

“Why are we doing all this when the most powerful person in these negotiations – the President – has failed to lead this debate or offer a serious proposal for spending and cuts that he would be willing to fight for?” West Virginia Democratic Senator Joe Manchin cried last week.

Mr. Obama’s aversion to risk is both temperamental and tactical. He would rather nudge his ideas forward through consensus than let the perfect become the enemy of the good. This infuriates his base. But it is music to the ears of the independent voters Mr. Obama needs to win in 2012.

The President’s change in tone partially reflects the power shift in Congress, where Republicans now control the House of Representatives. But it is also illustrative of the centrist guise Mr. Obama has increasingly striven to project since his new chief of staff Bill Daley took over in January.

In the run-up to last fall’s midterm elections, Mr. Obama repeatedly accused Republicans of driving the economy into the ditch when they were in power and insisted he would not give them back the keys. Now that they have them, Mr. Obama seems content to let Republicans go on a joy ride.

As House Republicans push through massive, ideologically driven spending cuts that would gut Planned Parenthood and public broadcasting, the White House is betting voters will appreciate the President’s more measured approach when they next go to the polls in 2012.

As Republicans prepare to unveil a fiscal plan that is likely to include controversial reforms to Medicare and Social Security, the White House is betting voter opposition to changes to the most expensive social programs will work in the President’s favour in 2012.

But there are risks for the President in appearing too passive. When asked who is taking a stronger leadership role, respondents to a Washington Post/ABC News poll released on Tuesday named Republicans in Congress over Mr. Obama, 46 per cent to 39 per cent.

Even if playing it safe does help Mr. Obama win re-election, it could come at the cost of building a legacy worthy of his promise.

“That’s a prescription for going down as another Bill Clinton,” American University historian Allan Lichtman said of Mr. Obama’s centrist approach. “Why not get engaged and make a difference for the country and the world? Why else become president? Just to get re-elected?”

No one will remember who Mr. Obama picked to win the NCAA basketball championship in 2012. Especially not the citizens of Libya or Japan.

Pakistan’s Musharraf: U.K. never told me not to torture

Associated Press | Mar 14, 2011

Former Pakistani President Pervez Musharraf said he believes Britain gave Pakistan “tacit approval” of its interrogation techniques on terror suspects.

In a program to be broadcast Monday, the British Broadcasting Corporation asked Mr. Musharraf if he remembers being told by the British government that Pakistani intelligence services should not use torture on British subjects.

Mr. Musharraf, who was president of Pakistan from 1999 to 2008, responded “Never, never once. I don’t remember it at all.”

He added: “Maybe they wanted us to continue to do whatever we were doing; it was a tacit approval of whatever we were doing.”

Human rights groups claim Britain colluded in the torture of terrorism suspects overseas. An ex-Guantanamo Bay detainee, Binyam Mohamed, who is of Ethiopian origin and became a British resident when he was a teenager, alleges Britain was aware he was beaten, subjected to sleep deprivation and had his genitals sliced with a scalpel while he was held in Pakistan in 2002.

Former UK security and intelligence co-ordinator David Omand, told the BBC that Britain does not practice torture and expects that its partners also respect that.

“I am very clear we are not and have not been complicit in torture and I’m in no doubt that all the countries concerned, including Pakistan and the United States, were very well aware of what British policy was, which was we don’t do this and we don’t ask other people to do it,” he said.

Deadly US strike in Pakistan kills another 38 civilians

Associated Press | Mar 17, 2011


MIR ALI, PAKISTAN – Pakistan’s army chief has condemned a US drone attack that killed more than three dozen people, saying the missiles struck a peaceful meeting of tribal elders.

Gen. Ashfaq Parvez Kayani called Thursday’s strike “unjustified and intolerable” and said it was a violation of human rights.

Pakistani intelligence officials initially said the 38 people killed in a compound in the North Waziristan tribal area were militants meeting to discuss the war in Afghanistan.

They spoke on condition of anonymity because they were not authorized to talk to reporters.

Civilian casualties from drone strikes are a main source of friction between the Pakistani and US governments.

Masood Kausar, the governor of northwest Khyber Pakhtunkhwa province, condemned the strikes and said the families of the victims should receive compensation.

“We have criticized drone attacks before and we will continue to raise our voice to condemn these attacks,” Mr. Kausar said.

The missiles hit a compound in the Datta Khel area of the North Waziristan tribal region — the main sanctuary for al-Qaeda and Taliban fighters along the Afghan border, Pakistani intelligence officials said.

A total of 38 people were killed and seven wounded, they said.

The US began firing missiles at militant targets in Pakistan in 2004, but the pace of the attacks picked up dramatically in 2008. Last year, there were around 120 strikes, which are believed to be carried out by unmanned drone aircraft launched either from Afghanistan or from inside Pakistan. There have been around 20 so far this year.

Most of the strikes this year and last have been in North Waziristan.

Washington does not acknowledge firing the missiles and reporters are barred from visiting the area, meaning it is hard to verify who is being killed. Pakistani leaders formally protest the strikes, but its intelligence agencies are widely believed to co-operate in some of them.

UN Security Council Authorizes Military Strikes on Libya

Resolution authorizes UN members to take “all necessary measures” to protect civilians and civilian centers; Gaddafi tells rebels that armed forces plan on taking over Benghazi; regime vows retaliation for intervention.

JPOST | Mar 18, 2011


NEW YORK – The United Nations Security Council voted Thursday to authorize military force against Libyan leader Colonel Muammar Gadhafi’s forces.

“Today the Security Council has responded to the Libyan people’s cry for help,” US Ambassador to the UN Susan Rice said. “This Council’s purpose is clear: to protect innocent civilians.”

The resolution demands the “immediate establishment of a cease-fire and a complete end to violence and all attacks, and abuses, of civilians.” The resolution stipulates that member states, upon notification to UN Secretary General Ban Ki-Moon and Arab League Secretary General Amr Moussa, can “take all necessary measures…to protect civilians and civilian populated areas, includingBenghazi, while excluding a foreign occupation force of any form on any part of Libyan territory.”

The Security Council’s authorization of the use of force also includes the enforcement of a no-fly zone to protect civilians, as well as an enforcement of the arms embargo, banning all international flights by Libyan owned or operated aircraft. The resolution also freezes the assets of certain individuals and five entities including critical state-owned Libyan companies. A newly established Libyan Sanctions Committee is empowered by the resolution to impose
sanctions on those who violate the arms embargo, including by providing Gadhafi with mercenaries.

“The future of Libya should be decided by the people of Libya,” Rice said in her remarks to the Security Council. “The United States stands with the Libyan people in support of their universal rights.”

The resolution was backed strongly by France, the United Kingdom and Lebanon. Ten countries voted in favor of the resolution. Russia, China, Germany, India and Brazil abstained.

“Our resolution is aimed to protect Libyan civilians,” Lebanon’s ambassador to the UN Nawaf Salam said. “It will not result in the occupation of even an inch of Libyan territory.”

The BBC has reported that raids conducted by unmanned drones could take place as early as Friday.

United Kingdom Ambassador to the UN Mark Lyall told the Security Council that the situation in Libya, as Gadhafi pushes toward the rebel stronghold of Benghazi, is now clear, and that “a violent, discredited regime which has lost all legitimacy is using weapons of war against civilians.”

“The international community has come together in deploring the actions of the Gadhafi regime and demanding that the regime end this violence against the Libyan people,” Lyall told the body. “The Libyan population want the same rights and freedoms that people across the Middle East and North Africa are demanding, and that are enshrined in the values of the United Nations Charter. Today’s resolution puts the weight of the Security Council squarely behind the Libyan people in defense of those values.”

The UN resolution came hours after Libyan leader Muammar Gaddafi threatened to storm the rebel bastion of Benghazi overnight, showing “no mercy, no pity”.

Al Jazeera television showed thousands of Benghazi residents in a central square celebrating the UN vote, waving anti-Gaddafi tricolor flags and chanting defiance of the man who has ruled for four decades. Fireworks burst over the city.

Gaddafi had warned that only those who lay down their arms would be spared vengeance to be exacted on ‘rats and dogs’.

“It’s over. The issue has been decided,” Gaddafi said. “We are coming tonight…We will find you in your closets. “We will have no mercy and no pity.”

Residents said the Libyan air force unleashed three air raids on the city of 670,000 on Thursday and there has been fierce fighting along the Mediterranean coastal road as Gaddafi moves to crush the month-old insurrection.

Rebel National Council head Mustafa Abdel Jalil told Al Jazeera television air strikes were essential to stop Gaddafi.

“We stand on firm ground. We will not be intimidated by these lies and claims… We will not settle for anything but liberation from this regime.”

Gaddafi’s Defense Ministry warned of swift retaliation, even beyond Libyan frontiers, if the UN voted for military action against the oil-exporting nation.

“Any foreign military act against Libya will expose all air and maritime traffic in the Mediterranean Sea to danger and civilian and military [facilities] will become targets of Libya’s counter-attack,” the ministry said in a statement.


Canada joins UN call for military action in Libya

Globe and Mail | Mar 17, 2011


Not since the Taliban was ousted from power in Afghanistan in the wake of 9/11 has the UN Security Council authorized military intervention, this time to save Benghazi from the advancing columns of Libyan forces loyal to the despotic and ruthless Moammar Gadhafi.

“All necessary measures” were approved to enforce a no-fly zone over Libya and protect the civilian population. That amounts to a mandate for bombing runs to destroy tanks and artillery bearing down on the rebel-held cities of Benghazi and Tobruk.

U.S., French and British warplanes were expected to launch initial combat patrols overnight, operating from bases in Cyprus, Sicily and – perhaps – Egypt. Canada will send six CF-18s, last in action in 1999 as they bombed Serb positions to protect the Albanians of Kosovo.

International willingness to undertake military action in support of self-styled, pro-democracy insurrectionists fundamentally recasts the Arab uprisings that swept Tunisian and Egyptian dictators from power. The protests there were mostly peaceful, but in Libya became a bloody civil war when Colonel Gadhafi’s regime brutally beat back rebels with mercenaries, tanks and artillery.

“We cannot let these warmongers do this; we cannot abandon civilians,” said Alain Juppé, Foreign Minister of France, which spearheaded the effort intervene militarily against Col. Gadhafi.

There were 10 votes in favour, no votes against, and five abstentions, including veto-wielding China and Russia as well as Brazil, Germany and India.

Russian Ambassador Vitaly Churkin said “there is a need to avoid such destabilizing developments,” calling the resolution “most unfortunate.”

Germany said it saw “considerable dangers and risks” in the military action and would not take part.

The vote happened only hours after a blood-chilling threat from Col. Gadhafi. “It’s over. We are coming tonight,” the Libyan leader told the residents of Benghazi on Thursday night in his latest rambling television broadcast. “We will find you in your closets; we will have no mercy and no pity.”

But shortly after the United Nations resolution passed, Tripoli was talking of a ceasefire with the rebels. “We are ready for this decision, but we require an interlocutor to discuss how to implement it,” deputy foreign minister Khaled Kaaim said at a news conference. It may be too little too late.

In Benghazi, the eastern city where the Libyan uprising was born, joyous residents thronged the main square, cheering the protection of a Western-led air armada, capable of wreaking immense destruction on the Libyan forces.

The resolution demanded an “immediate ceasefire,” but the most important language authorized nations “to take all necessary measures … to protect civilians … and civilian populated areas … including Benghazi.”

Warplanes from one or two Arab countries. – perhaps Jordan or United Arab Emirates – are expected to lead early raids to destroy Libyan radar sites and surface-to-air missile launchers in a symbolic, but important, effort to deny Col. Gadhafi the claim that he is under attacks by Western powers. As well, Egypt was shipping small arms and ammunition to the Libyan rebels, The Wall Street Journal reported.

U.S. President Barack Obama, who has prevaricated about a no-fly zone for several weeks, made no reference in his public appearances Thursday to adding Libya to the list of Muslim nations that the U.S. military was engaging, but Secretary of State Hillary Clinton said: “We want to support the opposition who are standing against the dictator.”

Col. Gadhafi seems to relish the looming military confrontation. “Any foreign military act against Libya will expose all air and maritime traffic in the Mediterranean Sea to danger and civilian and military facilities will become targets of Libya’s counterattack,” he warned.

But the Libyan air force is aging, ill-maintained and no match for modern warplanes. The last time Col. Gadhafi sent a pair of his fighters against a U.S. naval battle group – in 1986 – they were shot down before even coming close to the U.S. warplanes.

The UN resolution imposes a no-fly zone with exceptions for humanitarian flights. It also bans all flights by all Libyan aircraft anywhere, adds a number of Libyans to the list whose assets are frozen and calls for tougher enforcement of the arms embargo.

Several major states, including Russia, Germany, China and India, voiced misgivings over the use of military force, suggesting the intervention could escalate into a full-blown war and spill into other countries. All across the Arab world, simmering unrest has bubbled into uprisings, sometimes met with violence by existing regimes. In Yemen as well as Bahrain, government crackdowns have left protesters dead in recent days, although nowhere has the scale of violence matched the brutality of the Libyan regime’s response.

“The Security Council has responded to the Libyan people’s cry for help,” said Susan Rice, the U.S. ambassador the United Nations.

For the Obama administration, backing for the no-fly zone came after weeks of warning that it would begin with a bombing campaign.

“A no-fly zone begins with an attack on Libya to destroy the air defences and then you can fly planes around the country and not worry about our guys being shot down,” Defence Secretary Robert Gates said, when he first dismissed calls for military intervention as “loose talk.”

Monitors detect low radioactivity heading towards North America

The particles would continue across the Atlantic and eventually also reach Europe.

Reuters | Mar 17, 2011


Low concentrations of radioactive particles are heading eastwards from Japan’s disaster-hit nuclear power plant and are expected to reach North America in days, a Swedish official said on Thursday.

Lars-Erik De Geer, research director at the Swedish Defence Research Institute, a government agency, was citing data from a network of international monitoring stations established to detect signs of any nuclear weapons tests.

Stressing that the levels were not dangerous for people, he predicted the particles would continue across the Atlantic and eventually also reach Europe.

“It is not something you see normally,” he said by phone from Stockholm. But, “it is not high from any danger point of view.”

He said he was convinced it would eventually be detected over the whole northern hemisphere.

“It is only a question of very, very low activities so it is nothing for people to worry about,” Mr. De Geer said.

“In the past when they had nuclear weapons tests in China … then there were similar clouds all the time without anybody caring about it at all,” he said.

Before he spoke, the U.S. Nuclear Regulatory Commission advised any Americans living near Japan’s crippled Fukushima nuclear plant to move at least 80 kilometres away but it played down the risks of contamination to the United States.

“All the available information continues to indicate Hawaii, Alaska, the U.S. Territories and the U.S. West Coast are not expected to experience any harmful levels of radioactivity,” it said in a statement on Wednesday.

Mr. De Geer was commenting on data from the Comprehensive Test Ban Treaty Organization (CTBTO), a Vienna-based independent body for monitoring possible breaches of the test ban.

He said he believed the radioactive particles would “eventually also come here”.

The CTBTO has more than 60 stations around the world which can pick up very low levels of radioactive particles such as caesium and iodine isotopes.

It continuously provides data to its member states, including Sweden, but does not make the details public.

The New York Times said a CTBTO forecast of the possible movement of the radioactive plume showed it churning across the Pacific, and touching the Aleutian Islands on Thursday before hitting southern California late on Friday.

It said health and nuclear experts emphasized that radiation would be diluted as it travelled and at worst would have extremely minor health consequences in the United States.

In a similar way, radiation from the Chernobyl disaster in 1986 spread around the globe and reached the west coast of the United States in 10 days, its levels measurable but minuscule, the newspaper said. The CTBTO projection gave no information about actual radiation levels but only showed how a radioactive plume would probably move and disperse, it said.

Passengers on Flight From Japan Set off Radiation Detectors at US Airport

KTLA News | Mar 17, 2011

CHICAGO — Federal officials found traces of radiation on a United Airlines jet that arrived at Chicago’s O’Hare International Airport from Tokyo Wednesday but determined that the plane’s cargo and passengers were safe.

Mayor Richard Daley acknowledged Thursday that passengers on a flight from Tokyo had set off radiation detectors at O’Hare, but he offered no details and said federal officials will be handling the situation.

“Of course the protection of the person coming off the plane is very important in regards to any radiation, especially within their families and anything else,” Daley said at a downtown news conference to discuss his trip to China this week.

Federal officials inspected a United Airlines jet and one other with Geiger counters after they arrived in Chicago from Narita International Airport Wednesday, sources told the Tribune. A person familiar with the search said it was conducted by Customs and Border Patrol agents in the “guise of a random inspection.”

Though officials detected trace elements of radiation on two cargo containers on one of the planes, they later determined that the packages were safe, sources said. Officials also determined the jets were safe after inspecting for radiation.

The radiation plume forming over the Pacific from Japan’s nuclear crisis is a growing concern for U.S. carriers, who want to avoid contaminating aircraft surfaces and exposing passengers and employees to harmful radioactive isotopes.

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For the first time in recent memory, maps used to guide aircraft around hazards such as storms and active volcanoes now carry a red radioactive sign to denote a no-fly zone over the crippled Fukushima Dai-ichi reactors. Flight dispatchers Thursday were also given the coordinates of an area over the Pacific where airborne concentrations are of greatest concern, sources told the Tribune

The radiation alert in Chicago was first reported by the New York Post. The article had no details about the O’Hare incident but said another flight from Toyko also raised concerns at Dallas-Fort Worth International Airport. Tests on the Dallas plane showed low levels of radiation on luggage and in the jet cabin’s filtration system, according to the Post.

A source who had been briefed on the Dallas incident told the Tribune that some of the details in the Post story were inaccurate.

U.S. Customs and Border patrol agents did detect unusually high radiation in the cargo hold of an American Airlines plane returning from Tokyo, but found that the source was a shipment of medical equipment, said the person, who requested anonymity because he hadn’t been authorized to speak publicly of the incident.

No unusual radiation was found on passengers or the aircraft’s air intake system, he added.

Airline and government officials are reluctant to address their efforts to detect radiation contamination on U.S. aircraft at a time when some members of the public are jittery about possible fallout from Japan’s stricken nuclear plants.

Government officials don’t want to detail screenings routinely conducted for security reasons, sources said. Plus low-level radiation isn’t unusual on aircraft and may be linked to a variety of sources, including travel at high altitudes.

A spokeswoman for Chicago-based United Airlines declined comment and directed a reporter to the U.S. Customs and Border Patrol for information.

City Aviation Commissioner Rosemarie Andolino would say only: “We are aware that occurred yesterday. We are working with Customs and Border Protection on this issue.” She referred reporters to the Department of Homeland Security.

Following inquiries to press offices in Chicago and Washington, D.C., Customs and Border Protection said no flights coming into the U.S. had tested positive for unsafe levels of radiation. None of several press officers for the Department of Homeland Security or Customs contacted Thursday would answer questions about radiation levels at O’Hare or other airports.

Daley said the federal government has to set standards for dealing with radiation.

“Every city can’t have a policy. One says yes, one says no; you can’t do that,” he said. “You have to have a federal policy dealing with anyone entering the country with regards to situations like that, and they handle it very professionally.

“I can’t say yes or say no and pick one or the other. That will be up to the health and safety of everybody on the plane and those that have been detected, in regards to their family and other situations,” he said.