INNISFIL, Ont. - A massive multi-vehicle pileup has closed Highway 400 in Innisfil, just south of Barrie.

Provincial police say the highway is closed in both directions between Highway 89 and Mapleview Drive after this morning's multiple collisions.

Up to 60 vehicles may have been involved but no major injuries have been immediately reported.

The pileup happened after a snow squall moved into the region off Lake Huron and Georgian Bay leading to near whiteout conditions on the highway.

There is no word when Highway 400 will reopen.

Across southwestern Ontario, provincial police are reporting several highway closures, including a shutdown of Highway 402 in Middlesex County and Highway 401 in both directions in Oxford County.

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