One person was killed and at least four others were injured in a multi-vehicle crash that occurred as motorists slowed down or stopped for an earlier collision, police say.

One of the injured patients was airlifted to a trauma centre in Toronto, while three others were taken to local hospitals, said Ontario Provincial Police spokeswoman Const. Linda Wolf.

One person died at the scene of the four-vehicle crash, which occurred in Highway 400's southbound lanes, south of Highway 88, shortly after 7 a.m.

Investigators believe the crash occurred as vehicles slowed down or came to a stop because of a collision that occurred moments earlier.

As motorists slowed down or stopped, a minivan didn’t stop in time and crashed into the back of a car, which was pushed into two sport utility vehicles, police told CP24 reporter Cam Woolley.

An occupant of the car that was rear-ended was killed.

An Ornge spokeswoman said the patient who was airlifted to St. Michael's Hospital is a man in his 50's who suffered serious injuries. The man was later reported to be in stable condition.

Southbound Highway 400 reopened shortly after 11 a.m.

Weather not a factor, OPP say

Roads were reported to be slick at the time of the crash, as precipitation changed from snow to wet snow, Wolf said.

Police don't believe weather was a direct factor in the fatal crash, however.

With files from CP24 traffic and safety specialist Cam Woolley

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