Officials: Passengers on United flight out of Reagan National make emergency exit prior to take-off

Passengers aboard a United flight headed to Houston from Reagan National had to make an emergency exit from their plane before takeoff on Sunday after smoke came into the cabin, MWAA officials say.

Metropolitan Washington Aviation Authority officials say passengers from United flight 6122 had to exit from the plane via emergency slide after smoke appeared in the plane cabin as it taxied down the runway, preparing for take-off, around 1 p.m. Sunday.

Officials say the plane stopped and passengers had to make an emergency exit out of safety precautions.

Airport authorities say normal airport operations have resumed.

United Airlines tells The Washington Post that the issue affected a Mesa Airlines flight that operates under the United Express brand. The cause of the smoke was not immediately known.

All passengers and crew were placed on another flight to Houston. No injuries have been reported.

There has been no official word from United.