A 20-year-old man who was critically injured in a multi-vehicle crash in Vaughan is facing impaired driving charges, police say.

Eight people were taken to hospital when seven vehicles were involved in a crash at the intersection of Bathurst Street and Clark Avenue shortly after 10 a.m. on Thursday.

One of the injured, who had to be transported to a Toronto hospital by Ornge air ambulance, is under arrest on suspicion of impaired driving. He is in critical condition at Sunnybrook Hospital. He has since been released from hospital.

Police said the other victims were transported to hospital with "various levels of injury," and their conditions are unknown.

The sequence of events is so far unclear, but an SUV ended up on the roof of a sedan, which was pushed into a lamp post at the northwest corner of the intersection.

A gold coloured car had front-end damage and came to a stop in the middle of the intersection, and debris was scattered across the area. Police said the vehicle was being driven by the man who is under arrest.

Witnesses told CTV Toronto's Tamara Cherry that they saw the gold vehicle run a red light, starting a chain reaction. Police have not confirmed that account.

Police are investigating the crash scene which took up the entire intersection.

Luke Crawford has been charged with impaired driving, and dangerous driving causing bodily harm.