From an RTE article:

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 laser pens are powerful focused beams that can temporarily blind people if shon into an eye. Like this one. The FBI has issued a warning (scroll down) about it.