NEW YORK (CBSNewYork) — The Federal Aviation Administration is investigating after crews on four commercial flights reported seeing a drone as they approached the runway at Newark Liberty International Airport over the weekend.

The pilots flying commercial planes for ExpressJet, Northwest and two United flights all reported seeing the drone between eight and 13 miles from the airport Sunday afternoon, dangerously close to the aircraft, the FAA said.

Air traffic control tower audio captured the incident.

“Attention all aircraft use caution,” an air traffic controller warns. “Drone activity reported left side.”

A pilot is also heard telling the air traffic control tower about the drone.

Pilot: “Approach, Encompass 58-37, we just found a drone at 3,000 here.”

Tower: “Encompass 58-37– you saw the drone, what altitude you said?”

Pilot: “Three thousand feet, it was probably about 400 off the left wing.

Tower: “About how far off the left you said?”

Pilot: “About a quarter of a mile, it’s a red drone.”

None of the flights had to take evasive action and they all landed safely, the FAA said.

The FAA said it has seen a significant increase recently in pilots reporting drones near airports around the country. Last week alone, there were three reports in as many days of drones near John F. Kennedy International Airport.

Flying an unmanned aircraft anywhere near a plane is illegal and may result in fines of up to $25,000 and criminal charges.

Rob Feiner, a professional drone operator and owner of a company that sells the devices, said the pros are on the lookout for amateurs who knowingly break the rules.

“We will turn them in and will make sure that the FAA deals with them,” he said.

Many passengers are calling for stricter restrictions for drone operators who they say put their lives at risk, CBS2’s Janelle Burrell reported.

“That’s a crazy form of fun especially when you’re dealing with airliners that are coming in with hundreds of passengers a day,” David Brown of Hoboken said.

“If you see a bird outside that can bring down a plane too, but this is much more serious than that,” traveler Sunny Kim said.

There are drones with software that makes them inoperable inside designated no-fly zones. Some drone companies are suggesting that technology should be made universal with all unmanned aircraft.