WASHINGTON — Passengers at some overseas airports that offer U.S.-bound flights will be required to power on their electronic devices in order to board their flights, the Transportation Security Administration said Sunday.

The TSA said it is requiring some overseas airports to have passengers turn on devices such as cellphones before boarding. It says devices that won’t power up won’t be allowed on planes, and those travelers may have to undergo additional screening.

“As the traveling public knows, all electronic devices are screened by security officers,” the TSA said in the release announcing the new steps.

American intelligence officials have been concerned about new al-Qaida efforts to produce a bomb that would go undetected through airport security. There is no indication that such a bomb has been created or that there’s a specific threat to the U.S.

Homeland Security Secretary Jeh Johnson recently ordered the TSA to call for extra security measures at some international airports with direct flights to the United States. TSA does not conduct screening abroad, but has the ability to set screening criteria and processes for flights flying to the U.S. from abroad, according to a Department of Homeland Security official, who was not allowed to discuss the changes publicly and spoke on condition of anonymity.