The Department of Homeland Security has advised airlines of a potential new security threat involving possible attempts to attack passenger jets using explosives in shoes, and airlines were urged to pay extra attention to U.S.-bound flights from overseas.
Several officials familiar with the advisory say the "very recent intelligence" is considered credible. As a result, officials say, airlines will be paying extra attention to passenger shoes on overseas flights, and passengers may also get extra scrutiny in security checks.
The bulletin to airlines urges screeners to use the explosive trace detection swabs to check shoes.
The officials say the threat information was not specific to any particular airline, country or time. There is no indication of a specific plot, they say. But after assessing the information, the Department of Homeland Security advised airlines earlier Wednesday of the possible threat and urged greater security scrutiny on U.S.-bound flights.
One official described the level of concern over this new information as moderate.
"It's a reminder that we are under constant threat and an advisory to airlines: Be on their A game," said another official familiar with the threat intelligence.
The threat information is unrelated to the Olympics, several officials said.
In response to a question from NBC News, the Department of Homeland Security said it "regularly shares relevant information with domestic and international partners about relevant threat information as we work to meet our mission of keeping the traveling public safe."
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