FORT LAUDERDALE, Fla. -- A four plane pile-up at Fort Lauderdale Executive Airport is under investigation by the National Transportation and Safety Board.

Initial reports were that a pilot was behind the controls of the plane, but sources told Local 10 that a maintenance person was piloting the Sabreliner that went out of control and plowed into three other planes around 3 p.m. Friday.

Accident investigators will examine whether the plane's brake hydraulics system failed.

According to witnesses the propellers on the first plane, a Cessna, were spinning and clipped the left wing of the Sabre as it taxied the tarmac at the airport around 3 p.m. Two men on a tug were pulling the second plane when the Sabre approached, according to witnesses. The men then jumped off the tug leaving it to plow into the Sabre. Those two planes then collided with a third plane before coming to a stop, witnesses said.

No one was injured, according to officials.

"The only plane that was manned was the one that ran into the other planes," said Ted Lawson, spokesman with the city of Fort Lauderdale.

The incident happened on the north side of the airport in a parking area for airplanes.

The impact caused a fuel leak, which was sprayed down by the Fort Lauderdale Fire Department, officials said.