The westbound lanes of Highway 401 in Milton have reopened following a major collision involving at least 20 vehicles Wednesday afternoon.
Ontario Provincial Police said the crash took place just west of Martin Street near Highway 25 and was blocking all lanes.
Sgt. Kerry Schmidt said at least 15 passenger vehicles and seven transport trucks were involved in the collision. Police said no serious injuries were reported.
Police said they were advising motorists caught in the delay to stay inside their vehicles and wait for emergency responders to direct them away from the scene.
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Drivers were also urged not to use the shoulder to pass as it is reserved for emergency vehicles.
Police said some major roadways in the Greater Toronto Area are experiencing white-out conditions due to blowing snow.
“With the snow and slush on the roads, I was going through white-out conditions all the way up and the roads are slippery,” Schmidt said.