York Regional Police said officers were called to the intersection of Doane Road and 2nd Concession at 2:17 p.m. on Friday for reports of a vehicle rollover.
When police arrived, one person was found unconscious and was taken to hospital in life-threatening condition.
The other occupant of the vehicle sustained minor injuries and was not taken to hospital.
“The intersection is expected to be closed for several hours,” police wrote in a tweet.
More to come…