GEORGIAN BAY TOWNSHIP, Ont. -- Provincial police say a woman is dead and three people are injured after a single-vehicle collision in the Muskoka area.

Police say the crash happened just before 7 a.m. Friday in Georgian Bay Township, Ont.

They say a 42-year-old woman was pronounced dead at the scene.

Two passengers were airlifted to a Toronto-area hospital with life-threatening injuries, while the driver was treated at a local hospital for minor injuries.

Police say an area of Highway 400 was closed for several hours for the investigation.

It has since been reopened.