A federal safety agency says it's not investigating an airport collision involving two jetliners at Phoenix Sky Harbor International Airport.

The planes clipped wings Thursday evening, but there were no injuries to people. National Transportation Safety Board spokesman Terry Williams says the agency isn't investigating the accident because the damage to the planes was "very, very limited."

Officials say a departing Frontier Airlines flight was pushing back from its gate when it collided with an arriving Southwest Airlines flight.

The Fire Department says there was a fuel leak due to the collision outside Terminal Three.

The Frontier plane was headed to Denver, and the Southwest flight was arriving from Oklahoma City.