Provincial police say they fear for the lives of two people who were involved in a single-vehicle crash that sent four to hospital on the ramp connecting Montreal's Highway 40 and 15 South early Thursday morning.

Police were notified of the incident around 1:30 a.m. The vehicle transporting two men and two women, aged between 18 and 35, had struck a wall.

All four passengers were sent to hospital with serious injuries. Police say they fear for the lives of the driver and one passenger.

Sûreté du Québec (SQ) spokesperson Camille Savoie says speed may have been a contributing factor in the crash. Police also requested a sample kit from the driver to assess whether he was impaired behind the wheel.

SQ collision reconstruction experts were at the scene to try to determine the circumstances that led to the event. The affected roads reopened around 5 a.m.