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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The National Security Agency's director flatly denied a Washington Post report Wednesday that the NSA secretly broke into communications links to Google and Yahoo servers overseas.
Army Gen. Keith Alexander, the NSA director, pushed back against the report that cites leaked classified documents, saying the agency does not illegally access the servers of Internet companies.
"The servers and everything we do with those, those companies work with us. They are compelled to work with us. This isn't something the court just said, 'Would you please work with them and throw data over it.' This is compelled. And this is specific requirements that come from a court order," Alexander said at a cybersecurity conference in Washington.
"This is not NSA breaking into any databases. It would be illegal for us to do that. So, I don't know what the report is. But I can tell you factually we do not have access to Google servers, Yahoo servers. We go through a court order."
The NSA similarly denied the claim in a written statement to CNN saying, "The assertion that we collect vast quantities of U.S. persons' data from this type of collection is also not true."
"We have long been concerned about the possibility of this kind of snooping," said Google, "which is why we have continued to extend encryption across more and more Google services and links"
Yahoo said, "We have not given access to our data centers to the NSA or to any other government agency."