And it had to be from up above the plane! I mean pilots sit in "shadow zone" (so to speak) in relation to anything on Earth. So the only situation in which such laser could actually harm and burn someone eyes, is the source came from another plane, flying above. Its quite possible - so many times on my flights I see planes below me going the opposite way.
If your hypothesis was true -- that the pilots eyes are always obscured from the ground by the plane's fuselage -- it would also be impossible for the pilot to see any part of the ground from the cockpit. This is easily debunked with a Google image search of photos taken by pilots looking out cockpit windows.
