Two tractor trailers collided in the eastbound lane of Highway 401 on Tuesday afternoon.
The collision occurred between James Snow Parkway and Trafalgar Road near a construction zone that is part of the 401 expansion.
The tractor trailers then caught fire, leading to a massive blaze with thick black smoke.
Both lanes of Highway 401 just west of Trafalgar Road were shut down. The westbound lanes have since reopened.
Sgt. Kerry Schmidt says one of the tractor trailers was carrying dangerous goods and the other was transporting gravel.
One driver suffered burn injuries and was taken to the hospital. A second driver had minimal to no injuries.
A section of the highway was closed but reopened just before 1:30 a.m.
There is no word on what caused the collision at this time.