The crash happened at about 1:15 a.m. at the intersection of Vanier Parkway and McArthur Avenue.
One of the vehicles rolled over and the two young people inside were ejected by the force of the crash, according to Ottawa paramedics.
- A 24-year-old man suffered critical closed head injuries, neck injuries and multi-system trauma. He was unconscious and needed help breathing from paramedics when they arrived.
- A 21-year-old woman suffered critical, life-threatening head injuries and multi-system trauma.
In the other vehicle, the 39-year-old man behind the wheel suffered serious closed head injuries and a serious leg fracture. He was unconscious as he was being extricated from his vehicle by firefighters and was taken to hospital in critical condition.
All three were taken to the Ottawa Hospital’s Civic campus trauma unit.
The SIU investigates cases involving police that cause serious injury or death, as well as allegations of sexual assault, but the police watchdog has not said how police were involved.
Vanier Parkway is closed in both directions between Montreal Road and Donald Street. McArthur Avenue is closed between North River Road and Olmstead Avenue.