A falling tree at Johnston Canyon near Banff has seriously injured a 12-year-old boy.
It happened on the popular hiking trail Thursday afternoon, reports the Calgary Sun.
The boy was airlifted by a local helicopter company to the hospital in Banff and then picked up by STARS Air Ambulance and taken to the the children's hospital in Calgary.
Fatima Kawaja with STARS says the boy remains in hospital with life-threatening injuries.
"There was extensive trauma," she told the Calgary Herald.
The hiking trail is closed while investigators determine what caused the tree to fall.
With a file from the Canadian Press.