Passengers on a Metropolitan Area Express train in Portland, America, were stunned as they witnessed the door wide open while it travelled at high speed next to a motorway.
KOINlocal6.com reports that YouTube user Roz Miller said he was on the MAX in Portland's Hollywood District and that someone had tried to get onto the train just before it took off.
Miller said the person was knocked back by the train and wasn't able to board, but the door stayed open until the next stop at Lloyd Center shopping centre.
The footage shows one passenger even walking to the edge and sticking his head out of the window.
Mary Fetsch from TriMet, which operates the MAX train, told KOINlocal6news.com: 'Once the operator was alerted to the malfunction, the door was immediately disabled.
'This type of failure is rare and the train has been pulled from service as crews investigate. We always encourage the public to immediately alert the operator if they see any safety concern.'
Watch the video below:
Landslip warps train tracks and causes rail disruption in Yorkshire
Student cheats death after being hit by 90mph train while taking pictures
Video: Passenger hides in overhead luggage to avoid paying train fare