The Transportation Security Administration (TSA) is adjusting its security measures by asking some overseas aircraft passengers to “power up some devices, including cell phones,” said the agency in a statement today.

The increased scrutiny is in response to the directive last week from Secretary of Homeland Security Jeh Johnson to the TSA  to implement enhanced security measures at certain overseas airports with direct flights to the United States.

Security officers currently screen all electronic devices before travelers are allowed to board aircraft. Under the enhanced security examination, officers may ask travelers to turn on the devices. Powerless devices will not be allowed on board the aircraft. “The traveler may also undergo additional screening,” said the TSA in its statement.

There is a “deepening concern that terrorists in war-ravaged Syria are trying to develop a new generation of bombs that could be smuggled onto commercial planes,” according a report from ABC News.

“U.S. officials have been outspoken about the dangers posed by Al Qaeda in the Arabian Peninsula and — separately — the threat of foreign fighters in Syria, the latest intelligence shows that the two threats have bonded in an unusually powerful way, essentially creating a sum more worrisome than its parts,” says the ABC News report.

The intelligence regarding the potentially deadly partnership of Al Qaeda and Syrian fighters is part of the reason airlines were issued an advisory earlier this year to watch for toothpaste tubes, cosmetics and shoes laden with explosives.