FBI Probes Lasers Beamed at Plane Cockpits.

WASHINGTON - The FBI, concerned that terrorists could use lasers as weapons, is investigating why laser beams were directed into the cockpits of seven airplanes in flight since Christmas.

Laser beams can temporarily blind or disorient pilots and possibly cause a plane to crash.

The FBI is looking into two incidents in Colorado Springs, Colo., and one each in Cleveland, Washington, Houston, Teterboro, N.J., and Medford, Ore., according to federal and local law enforcement and transportation officials, some of whom spoke only on condition of anonymity.

A federal law enforcement official, who declined to be identified by name, said Thursday there is no evidence of a plot or terrorist activity. But pilots are troubled by the incidents, and the FBI earlier this month warned of the possibility that terrorists might use the devices as weapons.

“It’s not some kid,” said Paul Rancatore, a pilot who serves as deputy chairman of the security committee for the Allied Pilots Association. “It’s too organized.”

Loren Thompson, who teaches military technology at Georgetown University, called it a “rather worrisome development,” though he said experts would be more puzzled than alarmed.

“What we’re talking about is a fairly powerful visible light laser that has the ability to lock onto a fast-moving aircraft,” Thompson said. “That’s not the sort of thing you pick up at a military surplus store.”

Thompson said a piece of equipment that could do the things the FBI suspects would be “fairly expensive and fairly sophisticated.”