MONTREAL - Questions are being raised about commuter safety after a rider took a video that shows the metro speeding down the tracks with a door wide open.

A person who calls himself Maxime Perron posted the video to YouTube Monday evening, saying one door stayed open while the metro car ran on the green line for several stops between the Langelier and Frontenac stations.

He said nobody on the car pulled the emergency brakes because they did not want to be stuck between stations.

The Société de Transport de Montreal said the incident actually occurred for a single stop, between the Beaudry and Berri-UQAM stops on the green line.

STM spokeswoman Marianne Rouette said that once they were alerted to the problem they immediately took the metro out of service and sent it for testing.

"They repaired the broken pieces and sent them to the lab so there's an expertise that will be done," Rouette said. "We will know more about the cause maybe today, maybe tomorrow."

Rouette added that passengers should pull the emergency brake in such a situation in order to notify the driver.

She said the pulling the break will make the metro slow down to a safe speed before pulling to a stop at the next station.

Click the box below to see the video posted to YouTube.