A single-vehicle collision in Milton has left a woman dead.

OPP Sgt. Kerry Schmidt said officers received a call at about 12:30 p.m. Sunday about a single-vehicle crash in the westbound lanes of Highway 401 near Guelph Line.

First responders said they had to cut the roof off the vehicle in order to extricate the driver of a black Dodge Caliber.

The female driver, 39, from Kitchener, Ont., was the only person in the vehicle, Schmidt said.

She died at the scene.

Her name has not yet been released.

The right lane of the westbound 401 is closed, but traffic is still moving in the other lanes.

Any witnesses to the collision are encouraged to call the OPP at 905-278-6131.