Excessive speed and alcohol are being investigated as causes of a crash on Stoney Trail S.E. on Monday that sent five people to hospital and closed a stretch of the roadway for several hours.

Emergency crews were called to Stoney Trail west of 52nd Street S.E. just before 10 p.m.

Police say a blue Subaru Impreza was merging onto westbound Stoney Trail when it was hit from behind by a white Ford F350.

The Ford then went off the road and rolled, landing on its roof.

The driver of the F350, a 50-year-old man, was taken to hospital with serious, life-threatening injuries.

Three passengers in the truck, a 37-year-old man, a 23-year-old man and an 18-year-old man, all suffered minor injuries.

The driver of the Subaru, a 31-year-old man, also suffered minor injuries.

Alll five people were taken to hospital.

 “When officers arrived on scene it was a very chaotic scene at this point we are still determining who was in what area inside the vehicle and who played what role at the time of the collision,” said Acting Sgt. Jason Van Dorp with the Traffic Unit.