AUSTIN Texas: The Federal Aviation Administration and the US National Transportation Safety Board said they are both investigating an aborted aircraft landing in Austin, Texas this week involving a FedEx cargo plane and a Southwest Airlines jet, which were both cleared to land on the same runway.

Reuters reported that the two planes almost collided, as the FedEx plane, which was set to land, was forced to overfly the Southwest plane, which was cleared for take-off, to avoid a crash.

"Shortly before the FedEx aircraft was due to land, the controller cleared Southwest Flight 708 to depart from the same runway," the Federal Aviation Administration said.

"The pilot of the FedEx airplane discontinued the landing and initiated a climb out," it added.

Flight tracking website data indicated that the the two airplanes came very close to colliding, but it was not clear precisely how close.

Because of the ongoing investigations, Southwest has declined to comment, but FedEx said its flight "safely landed after encountering an event."