MONTREAL -- One person was seriously injured and Highway 40 westbound was closed for a 15-kilometre stretch east of Montreal as a result of a series of car pileups involving dozens of cars.

Quebec provincial police say there are three separate sites involving 10 to 15 vehicles each, for a total of about 40 cars caught in the mix.

Two people have minor injuries, as well as one seriously injured but not in critical condition.

The incident began with a first crash Friday at about 12:20 p.m. in Saint-Sulpice, near Repentigny, in the Lanaudière region.

At least one person was seriously injured, though officials say they are expected to survive. Tow trucks, ambulances and fire trucks are all at the scene.

Highway 40 was closed westbound for about 15 kilometres between Lavaltrie and L'Assomption. It was reopened later Friday.

Quebec provincial police are warning drivers to slow down and use caution on roads in the greater Montreal area, and to delay any non-essential travel for the moment. Visibility on the roads is reduced as a result of blowing snow.

- With files from The Canadian Press