An airline captain says an unmanned drone came within 200 feet of his jet over New York.

The FBI is now asking for the public's help, for any information about the unusual and potentially dangerous incident.

Brian Todd has the latest.

On approach to New York's JFK Airport, an Alitalia AIirlines captain spotted something very close to his jet.

Here's what he said to the control tower.

(TOWER:"What did you see?"

(AZ PILOT: "We saw a drone, a drone aircraft.."

(TOWER: "Alitalia.. Roger. What altitude did you see that aircraft?"

(AZ PILOT: "About one thousand five-hundred."

The FBI now says the unmanned drone came within 200 feet of the passenger plane.

Alitalia says the co-pilot spotted it too. The flight landed safely.

The incident Monday afternoon is now under investigation by the Federal Aviation Administration and the FBI, which is asking for the public's help in finding the aircraft and its operator.

A source with knowledge of the incident says investigators have interviewed the pilot and others on board the Alitalia plane.

The pilots of two other jets, which were approaching JFK at about the same time, said they didn't see the unmanned aircraft.

Experts says even small drones can pose a risk to commercial jets, if they collide with them or get sucked into their engines, like birds sometimes do.

The incident also raises questions about rules governing these vehicles.

"Unmanned aircraft can be as small as this drone, or smaller, or as big as a passenger plane.  According to the FAA, you can fly them for recreation like this, but not more than 400-feet off the ground, and not near an airport," CNN Reporter Brian Todd says.

Is an operator does fly one ithin three miles of an airport, he or she has to let air traffic control know.

Experts say most drones are small, weighing only about five pounds and are made of a carbon-fiber substance, meaning many of them can't be detected by radar.

They're not allowed to fly in restricted airspace, but could a terrorist weaponize one and attack places like New York and Washington anyway?

"Well I think some classified programs that the Department of Defense operates in the District of Columbia could potentially detect and neutralize a drone or a manned aircraft going into that airspace," says Alan Frazier, an aerospace expert at North Dakota University.

Frazier says a big concern he has, is more people are using drones in unauthorized ways. breaking the rules. He says even media entities like paparazzi, trying to get photographs of celebrities. have at least inquired about using drones, and he's heard o documented cases where they've used them.