CALGARY -- RCMP are searching for a suspected impaired driver who is believed to have fled a crash scene on foot Friday morning along the Trans-Canada Highway west of Calgary.

Cochrane RCMP officials confirm an investigation began early Friday following reports an allegedly intoxicated man had entered a store near the Highway 1 and Highway 40 interchange and stole several items. Witnesses say the suspect drove off in a grey Dodge Ram.

Following the theft complaint, RCMP received several complaints of a vehicle matching the description driving erratically, including travelling westbound in the eastbound lanes of the Trans-Canada Highway.

The Dodge Ram was not located until it collided with a semi on the highway near Range Road 33, just west of Calgary city limits. RCMP say both vehicles were travelling eastbound at the time of the crash and the pickup truck had smashed into the back of the semi before leaving the road and flipping.

Emergency crews arrived and located two passengers — a man and a woman — suffering from minor injuries, but the driver of the pickup was nowhere to be found. RCMP suspect he fled the area on foot.

The driver of the transport truck was not injured.

RCMP continue to investigate the theft, erratic driving reports and crash. Anyone with information regarding any of the incidents is asked to contact the Cochrane RCMP detachment at 403-851-8000 or anonymous tips may be submitted to Crime Stoppers.