Four people from Calgary were taken to hospital after a rollover collision northeast of the city.
Around 6:00 p.m. Sunday, Airdrie RCMP responded to the accident in a field northeast of Calgary near range road 285.
Reports say a truck lost control and rolled, injuring four occupants.
A 19-year-old passenger suffered serious life threatening injuries and was airlifted via STARS to hospital.
The three other occupants were taken to hospital by ambulance with non-life threatening injuries.
The investigation is ongoing.