The Calgary Police Service traffic unit is investigating an afternoon crash involving a commercial vehicle and a Ford Focus on the west side of the city that seriously injured two people.

According to EMS spokesperson Naomi Nania, the crash occurred shortly after 2:00 p.m. on Highway 8 (Glenmore Trail) near the intersection with 69 Street Southwest.

EMS transported the occupants of the Ford Focus from the crash scene to the Foothills Medical Centre. The driver, a woman in her mid thirties was considered to be in serious, potentially life threatening condition while the passenger, a woman in her early fifties, was transported in serious but stable condition.

Nania confirms the two occupants of the car are related.

A third patient, the man driving the commercial vehicle, was assessed at the scene but did not require additional medical treatment.

As of 3:00 p.m., the eastbound and westbound lanes of Highway 8 have been closed to traffic between 69 St. S.W. and Sarcee Trail.