US investigators are reported to be examining a spate of cases in which laser beams have been shone into the cockpits of aircraft.
The most recent case was in Cleveland, Ohio, where a pilot says a green laser light was shone through the window of his cockpit.
The light tracked with the plane for several seconds as it came in to land.
The FBI is said to be concerned that terrorists may use lasers to stun and disorientate pilots and is investigating at least six similar incidents involving lasers.
However, authorities say they have no specific intelligence to link the incidents with al-Qaeda activities in the US.
