Peel Regional Police responded to a single-vehicle crash in the area of ​​Elmvale Avenue and Conestoga Drive on Saturday just after 2 a.m.
Police said a vehicle crashed into a tree and burst into flames.
Three occupants of the vehicle were located and pronounced dead at the scene, police said.
More details about the victims have not been released.
The cause of the collision is unknown.
Conestoga Road is closed at Sandalwood Parkway for investigation.
This is a developing story.