NEWMARKET, Ont. – One person is in hospital with life-threatening injuries after a crash north of Newmarket involving a tractor-trailer and three vehicles, Tuesday morning.
    
Police say the collision occurred around 7:30 a.m. on Davis Drive in East Gwillimbury.
    
Investigators closed the road from Warden Avenue to McCowan Road as they probed the incident.

There is no word on what caused the crash.