Whiteout conditions from a massive, wind-fueled snowstorm led to some multiple-vehicle pileups on southern Ontario 400-series highways.

One chain-reaction collision at Aurora Road has left southbound Highway 400 closed on Friday morning for three hours, re-opening after 2 p.m..

"We were sliding, and we just managed to stop before we hit it, and then the transport hit us from behind," one participant said at the scene.

At least five people were sent to hospital with serious injuries following that collision, which occurred about 11 a.m. when a tractor-trailer unit jackknifed. That led to several other vehicles piling into each other, said OPP Sgt. Dave Woodford.

Fifteen others were injured, with 25 vehicles involved in the chain-reaction event, he said.

None of the injuries were life-threatening. Paramedica treated "multiple walking wounded" in an emergency medical services bus, he said.

Charges will likely be laid in connection with the accident, Woodford said.

There were numerous accidents on the 400 near Innisfil, CTV Toronto's Naomi Parness reported.

Woodford said  that between 6 a.m. and 10:45 a.m., officers had attended 70 crashes on OPP-patrolled highways, "and the snow only really began coming down at 9 a.m."

By late afternoon, the number of reported accidents had risen to 225. Woodford said the majority of those were "unnecessary" and resulted from bad driving.

"People were driving by me as if they were indestructible," he said. "You've got to slow down, have some sense."

OPP Commissioner Julian Fantino added: "Too many drivers are not adjusting to the weather and road conditions. It is no mystery to me why the number of single motor vehicle crashes are starting to mount up."

Fantino said he would propose absolute liability legislation under the Highway Traffic Act so that irresponsible drivers could be held accountable.

Train accident

Late Friday afternoon, an accident involving a train and three vehicles left no one injured.

A freight train clipped the very rear of a northbound Brampton Transit bus in the curb lane at a crossing as the bus was clearing the tracks, Const. J.P. Valade, a spokesperson for Peel Regional Police, told ctvtoronto.ca.

As a car in the passing came to stop on the tracks for other traffic, the traffic barrier started to come down. The occupants got out before the train struck it. "There was a significant collision with the vehicle," he said.

A tractor-trailer in the southbound lanes at the tracks got struck by the resulting debris, with the barrier arms getting damaged, Valade said.

Police are investigating further, he said.

Hamilton-area troubles

An accident and weather-related road problems affected road travel in the Hamilton-Burlington area.

At about 4 p.m., a transport truck jackknifed in the northbound lanes of the QEW at Burlington Street in Hamilton. It struck the right-side cement barrier. About 500 litres of diesel fuel spilled onto the roadway.

The driver wasn't injured and no charges are expected.

Highway 6 from Highway 403 to Highway 6 had to be shut down at 11:15 a.m. after more than 60 transport trucks found themselves unable to travel up the hill.

The OPP expected both trouble spots to be cleared up by 7 p.m.

With files from The Canadian Press