DENVER (CBS4) – A Denver firefighter was hurt trying to get to a man believed trapped inside a burning home early Sunday morning.

The fire in the 4600 block of Atchison Way broke out shortly after 2 a.m. Crews tried to reach the second floor but found the stairway was impassable.

The man they were looking for was out of town.

The firefighter realized he had to get out of the house and fell two stories. He was treated at the scene for burns and cuts.

There was so much damage the house is in danger of collapsing. The cause of the fire is being investigated.