RCMP say two people were killed after a collision involving two cube vans, a car and a semi truck on Highway 1 between Calgary and Canmore on Wednesday morning.
Investigators believe a cube van was headed east when it veered through the median and into the westbound lanes, colliding with a white car, which was then rear-ended by a semi truck.
Another westbound cube van then collided with the semi.
The two occupants of the car were killed in the crash.
The drivers of both cube vans, as well as a passenger in the eastbound cube van, were taken to hospital with non-life-threatening injuries, police said.
Photos from the scene show one semi-truck lying on its side across the highway and a badly damaged five-tonne truck in the ditch.
Investigators were still at the scene as of 2:25 p.m., and traffic was still being rerouted through Morley Road to Highway 1A. Drivers were being asked to avoid the area.
In a tweet just after 11:30 a.m., 511 Alberta noted the westbound lanes of the Trans-Canada Highway were closed due to a semi rollover.
Shortly after 8:30 p.m., the RCMP provided an update and said emergency crews had cleared the scene and that westbound traffic on Highway 1 could resume normal travel.