A section of Highway 401 that police closed after a crash late Wednesday was open in time for Thursday's morning rush.

OPP Const. Dave Woodford said Thursday that the stretch of highway in the city's east end was reopened at about 6:30 a.m.

A 20-year-old woman was badly injured in the chain-reaction collision, which began at about 11:50 p.m. when a car got a flat tire and parked on the shoulder of the express lanes between Warden Avenue and Brimley Road.

It was hit by a second car and pushed into traffic, where it was hit by a transport truck. Police say a third car was also involved.

The victim has life-threatening injuries and remains in hospital, said Woodford.

Two other people received minor injuries.

Alcohol is not believed to be a factor in the crash. Police have not said whether they will lay any charges.