The OPP is investigating an accident involving a single vehicle that left one person dead and three injured on Thursday evening on Highway 11 near Gravenhurst.
According to the police, the driver who was driving north lost control of his vehicle before making a roll and finding himself in the ditch.
The death of one of the occupants of the vehicle was noted on the scene.
Two wounded were rushed by ambulance helicopter from Ornge to a hospital in Toronto.
A third person was treated in a local hospital. His life is not in danger.
The police have not given more details for now.