A man was killed in a four-vehicle crash on Hwy. 427 in west Toronto early Thursday, provincial police say.

The collision happened in the early morning hours when blowing snow had created slippery conditions on roads throughout the GTA, according to OPP Sgt. Kerry Schmidt.

A transport truck broke down and was partially blocking a southbound lane when three other vehicles crashed into it, he said.

The 32-year-old Mississauga man was pronounced dead at the scene. He was on his way to a hospital at the time of the collision, Schmidt said.

The police investigation closed lanes on Hwy. 427 for several hours overnight.

Schmidt cautioned that there are closures and collisions in various parts of the GTA as the morning rush hour peaks.

Another driver was critically injured on Hwy. 401 westbound just past Dixie Road when they slammed into the back of a stopped transport truck, he said.

There are also multiple crashes in the are of Hwy. 401 westbound near Hurontario Street.

“Make sure you clear your vehicle before you head out. Be aware of changing traffic conditions and patterns because of closures that are happening really across the area right now,” Schmidt said in a video posted to Twitter.