(AP) — Air travelers may have their hands swabbed more often as part of a stepped-up effort to screen passengers for explosives, an Obama administration official said Wednesday.

Airports were told Wednesday that more passengers should be randomly screened for explosives before, during and after they go through metal detectors, the official said. The screening could include swabbing travelers' hands or their carry-on luggage to check for traces of explosives, said the official, who requested anonymity to speak about security plans.

The heightened screening follows a Christmas Day attack on a Detroit-bound airliner. A Nigerian man accused of being trained by al-Qaida operatives has been charged with trying to blow up the plane with explosives hidden in his underwear.

Other security measures have been enhanced since the December attack. Heightened screening measures have been tested at five airports over the past month.

TSA spokeswoman Kristin Lee said the stepped-up screening is random and that travelers will not see the same procedures at all airports.

From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook. Credit: Newsday/Howard Schnapp, Kendall Rodriguez, Drew Singh; Anthony Florio, Randee Daddona, Morgan Campbell, Debbie Egan-Chin

Get ready for sun and fun with NewsdayTV's summer FunBook special! From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook.

From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook. Credit: Newsday/Howard Schnapp, Kendall Rodriguez, Drew Singh; Anthony Florio, Randee Daddona, Morgan Campbell, Debbie Egan-Chin

Get ready for sun and fun with NewsdayTV's summer FunBook special! From celebrating America's 250th birthday to a new ride at Adventureland, NewsdayTV's Elisa DiStefano and Newsday lifestyle editor Meghan Giannotta have your inside look at Newsday's summer FunBook.

SUBSCRIBE

Unlimited Digital AccessOnly 25¢for 6 months

ACT NOWSALE ENDS SOON | CANCEL ANYTIME