A person has critical injuries following a collision in Caledon early Tuesday morning.
The incident happened at around 1:30 a.m. on Highway 9 near Humber Station Road.
The Caledon Ontario Provincial Police department said two vehicles collided and one driver sustained life-threatening injuries.
The driver was airlifted to a trauma centre.
The cause of the collision is unknown.
Highway 9 remains closed in both directions as police investigate.