Police are investigating after a man in his mid-twenties was dragged underneath a CTrain in Calgary on Tuesday afternoon.

Investigators said the man was hanging from a side mirror on a middle car of the CTrain before he lost his grip when it started to pull out from the Centre Street stop. The man fell underneath the moving vehicle where he was dragged before the CTrain stopped.

Calgary Transit arrived at the scene and uncoupled the train cars so that emergency workers could remove the man pinned underneath. The entire extrication process took almost an hour. Emergency officials told CTV Calgary that the man was conscious during the removal and that he was transported to Foothills Hospital with serious to life-threatening injuries.

“The patient did suffer multiple traumatic injuries as a result of being trapped and partially dragged by the train,” Stuart Brideaux of Calgary EMS said. “Another concern we had with the prolonged extrication was that he was lying on the cold pavement so hypothermia did become a concern as well.”

Calgary police speculated that the man may have been performing stunts before he fell below the train. Brideaux said police and transit officials have access to surveillance equipment along the train’s route.

“It doesn’t appear that it was an intentional act by the man, however that is still under investigation,” Brideaux said.

With files from CTV Calgary