(CNN) The F-B-I is paying cash to help cut down on "Laser Attacks" at airports. Last December, two pilots with JetBlue reported these attacks happened to them at Palm Beach International airport.
The federal government agency says it's getting more reports every year of people pointing lasers at planes. Nearly 4,000 of these incidents were reported around the country last year.
There's a $10,000 reward for anyone who reports people doing this. Thought it takes work to track down the source of the laser, it can be done with a helicopter, a dispatcher and squad cars.
CNN found the FBI has detained mostly teenage boys and men in their 30's, who face a possible five years in prison and a $250,000 fine.
And the FBI is not the only one posting a bounty on them.
For the next two months, 11 U.S. cities and San Juan, Puerto Rico, are offering up to $10,000 for information leading to arrests.
Attacks are particularly common in New York and Los Angeles, and they often obstruct the work of the targeted pilots.
"When a laser light flashes across the cockpit, it's about 25 percent brighter than a flashlight flashing in your face. So what that does is, that can cause temporary incapacitation," said Stephen Woolery, an FBI agent pursuing laser pranksters.
The consequences can be much worse than just annoying.
A pilot coming in for a landing at JFK two years ago radioed the tower right after an attack.
"We just got lasered up here," he said. "Two green flashes into the cockpit. It caught the first officer's eye."
A direct hit can burn the cornea, and that has put pilots in the hospital.
So far, no laser strike has been known to cause a pilot to crash an aircraft.
But the FBI fears it is only a matter of time.