Clean-up crews are currently at the scene of a truck rollover on Highway 401.
Ontario Provincial Police say the commercial vehicle had a tire blow out in the westbound lanes, between Guelph Line and Highway 6, causing it to roll over into a ditch.
The driver was transported to hospital with serious, but non-life-threatening, injuries.
OPP say one of the westbound lanes remains closed at this time while crews remove the truck.
Two other westbound lanes remain open, but OPP are warning drivers that traffic is backed up for approximately 10 kilometres and is moving slowly.
The closure is expected to end around 2:30 p.m.