A 35-year-old man was taken to the hospital after falling at least "several stories" while climbing Calderwood Butte in Peoria.
Peoria Fire officials say the man was climbing the side of the mountain without ropes when he fell. Fire crews say he fell so far that a set of car keys dropped during the fall were damaged and bent.
The man was unable to say how far up he had climbed.
A bystander reportedly stayed with the victim and guided rescue crews to him.
He reportedly suffered serious injuries to multiple parts of his body and was airlifted to a trauma center in critical condition.
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