Five young women are in hospital fighting for their lives after a single-vehicle rollover on Highway 401 early Friday morning.

The victims, who are all 20 years old and from Richmond Hill, were travelling east on Highway 401 near Dixie Road at about 2 a.m. when the vehicle they were riding in crashed into a cement guardrail and then rolled several times. The car came to a rest in a ditch.

The vehicle was moving into the express lanes from the collectors when the crash occurred, police said. The eastbound transfer lanes near Dixie were closed for hours for investigation. The cause of the accident has not been determined.

"Three of (the women) in the backseat did not have their seatbelts on, and two of those three were ejected from the vehicle," said Ontario Provincial Police Const. Dave Woodford.

All five women remain in critical condition. Police believe they were on their way home from a night out in Mississauga at the time of the crash.

The car was totalled from the impact.

With a report from CTV Toronto's Jim Junkin