A police spokesman says detectives have determined the people in the car are a couple in their 50s from Montreal.
A passerby reported seeing them in the parked vehicle along the southern slope of Mount Royal.
Police said little else about the cause of death — except that they didn't believe anyone else was involved. They found a gun near the bodies but wouldn't say if it was inside the car.
Const. Dany Richer says detectives are working to determine whether the couple took their own lives or if it was a murder-suicide.
The incident caused a road closure Friday, cutting off a main artery that leads to two hospitals — the Shriners and the Montreal General.