The Obama administration is stepping up security for some flights headed to the United States from Europe and the Middle East, reflecting heightened concern that terrorists are developing more sophisticated bombs designed to avoid airport screening.
Homeland Security Secretary Jeh Johnson said in a statement that he has directed the Transportation Security Administration to "implement enhanced security measures in the coming days" at selected overseas airports.
"We will work to ensure these necessary steps pose as few disruptions to travelers as possible," Johnson said in a statement. "We are sharing recent and relevant information with our foreign allies and are consulting the aviation industry."
Specific steps or airports were not disclosed. A homeland security official said that TSA would work with airlines and security agencies overseas and that the changes will primarily focus on airports in Europe and the Middle East.
The effort does not involve changes to what travelers can take aboard flights. But passengers may see additional inspections of shoes and electronics, additional use of scanners designed to detect trace amounts of explosives, and another stage of screening at boarding gates, in some cases, the official said.
The measures do not involve U.S. domestic flights, and passengers could see changes as early as next week.
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Three Secret Service agents were sent home after one of them was found passed out after a night of drinking in Amsterdam, an official familiar with the incident told CNN.
The agents were in the Netherlands as part of a contingent preparing for President Barack Obama's visit there this week.
According to the official, one Secret Service agent was found intoxicated and passed out in the hallway of his hotel. Hotel staff subsequently alerted U.S. authorities.
This agent and two other agents - who were his companions on a night out drinking in the Dutch capital - were disciplined by being sent home Sunday for not exercising better judgment.
Confirming that three agents went home for disciplinary reasons, Secret Service spokesman Edwin Donovan added an investigation is underway.
The story was first reported by The Washington Post.
The agents are blamed for not doing more to prevent another embarrassment for the 150-year-old agency, whose mission includes investigating crimes such as counterfeiting and credit card fraud in addition to protecting top U.S. figures, including presidents.
One of the biggest, most recent black eyes came nearly two years ago and also involved an advanced team ahead of an Obama visit to Colombia for the Summit of the Americas.
In that case, Secret Service agents hit the clubs of Cartagena for a night of drinking that ended with bringing prostitutes back to their hotel.
The agency immediately pulled 11 agents allegedly involved in the scandal from Obama's security detail, put them on administrative leave and removed their security clearances. In addition, 12 military personnel also were cited for their role.
Several government reports later examined the incident, looking into not just what happened but how the Secret Service handled the matter.
The agency has instituted tougher disciplinary rules in the wake of the Cartagena scandal.
A no-frills beachside condo tower isn't where you'd expect to find the world's most wanted drug lord.
But that, authorities said, was where they captured Joaquin "El Chapo" Guzman over the weekend.
His nickname, which means "Shorty," belies the tall and near-mythic status Guzman achieved in recent years for his ability to elude capture by using bribes, safe houses and an army of cartel helpers.
The early morning operation in the Mexican Pacific resort town of Mazatlan marked a dramatic twist in a case that has long captivated the country and frustrated investigators on both sides of the U.S.-Mexico border.
Authorities had been closing in on the notorious Sinaloa cartel leader for months before Mexican marines swooped in Saturday, Mexican Attorney General Jesus Murillo Karam told reporters.
A U.S. government warning this week to airlines about possible shoe bombs represents a credible threat linked to al Qaeda, officials told CNN.
Recent intelligence points to tactics believed to be tied to al Qaeda in the Arabian Peninsula and its master bomb-maker Ibrahim al Asiri, a federal law enforcement official said.
Counterterrorism officials don't believe there is an active plot in the works. But the law enforcement source said the United States periodically receives information on attempts by those believed to have been trained by Asiri to try to develop bombs that could defeat screening systems.
It's not a new threat, but one viewed as ongoing because they know the al Qaeda unit based in Yemen is constantly trying to improve its bombs.