Two people were airlifted to Canberra Hospital after a head-on collision between a near Cathcart on Friday.
Emergency services rushed to to Mount Darragh Road at 2.45pm after reports of a Ford Fairlane and a Toyota Corolla colliding.
The vehicles were travelling in opposite directions when the crash occurred.
A 23-year-old man, who had been behind the wheel of the Ford, was trapped in his vehicle when police and paramedics arrived.
Once freed, he and the 70-year-old female passenger of the Corolla were airlifted to Canberra Hospital in a critical condition.
The young man suffered serious head, chest and internal injuries, as well as a suspected fractured leg, while the elderly woman sustained suspected internal injuries in the crash. Both were treated by paramedics at the scene before being flown out.
The remaining patient - a 70-year-old man who was driving the Corolla - was taken by road ambulance to Bega Hospital to be treated for a broken collarbone and abdominal pain. He was later transferred to Canberra Hospital.
Cooma detectives are investigating the circumstances surrounding the crash and urge anyone with information relating to the incident to contact Crime Stoppers on 1800 333 000.