Terrorism possible but no solid leads in downed EgyptAir flight

NEW YORK -- Despite multiple layers of security at airports, terror groups in North Africa and the Middle East are obsessed with targeting planes.

If EgyptAir was brought down by terrorists, how could they do it?

Nearly 15 years after 9/11, terrorist organizations remain fixated on attacking the West and its allies by crippling commercial aviation.

There was the 2010 failed attempt by al Qaeda in the Arabian Peninsula to blow up U.S.-bound cargo planes with bombs embedded in printer cartridges.

Last year ISIS claimed a soda can bomb with a detonator and a switch had downed the Russian metrojet plane over Egypt in February .

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The terrorist group Al Shabaab was suspected of planting a bomb in a laptop blowing a hole in this jetliner shortly after it took off from Mogadishu, Somalia.

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A month later, another laptop bomb shattered windows when it exploded near a small Somali airport.

U.S. officials say that given terrorists' obsession with aviation, it's possible they could be behind what happened to EgyptAir flight 804 early Thursday.

The EgyptAir jetliner was en route from Paris to Cairo with 66 people aboard, when it swerved wildly in flight and crashed in the Mediterranean Sea, authorities said. Egyptian and Russian officials said it may have been brought down by terrorists.

"It raises my suspicion level ... that it was something other than a mechanical," like an explosive, said John Halinski, former deputy administrator of the TSA. He says that terrorists have been doing their homework.

"They understand our tactics, they study, they study the security policies of the TSA and other organization... a device planted on the inside of an aircraft at the right location with a timing device that is conceivable. That is not that difficult to do, especially if you're looking at locations that don't have as what you would define as the top security in the world."

U.S. investigators have been scanning social media and other sources for claims of responsibility, but so far there seem to be no signs of boasting.