Two teenagers, aged 16 and 18, have died after their car flew off an overpass on the Decarie Expressway.

According to the independent bureau of investigation (BEI), the car was flagged to stop at 2:20 a.m. Friday by Quebec provincial police as it was heading southbound on the highway.

The driver refused to stop and exited at the Sherbrooke Street entrance before U-turning to head back northbound.

Officers chased the vehicle, but lost sight of it and say that's when the car lost control and fell off the overpass.

"The vehicle was finally found in a serious accident on Highway 15 North, near Sherbrooke Street," the BEI states.

The two people in the car have been confirmed dead.

The BEI is investigating the incident as it involves police officers from the Sûreté du Québec (SQ).

Officers with Montreal police (SPVM) have been called in to support the investigation and will provide a scene reenactor to determine the circumstances leading to the crash. 

The area is currently closed to traffic.