The Ontario Provincial Police said the westbound express lanes on Highway 401 are closed at Highway 404/DVP following a transport truck rollover early Wednesday.
The rollover happened just after 3 a.m. and no other vehicles were involved, OPP said.
Shortly after 7:30 a.m., OPP Sgt. Kerry Schmidt said vehicle cleanup and guardrail repairs are underway.
Workers are in the process of uprighting the truck and the ministry of transportation is working on repairing the guardrail. The road is also being assessed for a possible diesel spill, Schmidt said.
The driver of the truck was taken to hospital with minor injuries.
The express lanes are expected to remain closed until 2 p.m. for the cleanup.