An Airmedic air ambulance MBB-Kawasaki BK117 helicopter crashed into a lake near Natashquan, Quebec, around 22:30 on Friday during a medical evacuation.
Of the five people on board (four crew members and one passenger), one pilot was rescued with non-life-threatening injuries, while four remain missing.
Search efforts are ongoing, and both the Sûreté du Québec and the Transportation Safety Board are investigating the crash.