MOSES LAKE - Three firefighters from Grant County Fire District 5 were inside a burning home when a portion of the roof collapsed onto them Thursday afternoon west of Moses Lake. They weren't injured.

About 4 p.m., fire crews responded to a report of a structure fire in the 4000 block of Road F Northeast and Road 4 Northeast near Mae Valley.

The fire appeared to have started near the front door of the double-wide mobile home, Chief Dan Smith said, near some sort of wooden box, possibly a planter.

Smith said the fire spread up the outer wall and onto the roof. Much of the property inside was undamaged by the fire and firefighters were able to move some of the furniture out of the home.

While three firefighters were inside the home, a portion of the roof caved in, falling on top of them. The three men were covered with debris but uninjured. An ambulance crew from AMR was on scene in case of dehydration or heat stroke.

Crews continued to battle the blaze for more than two hours, citing the large amount of insulation in the vaulted ceiling that continued to spread the fire throughout the roof.

Several more sections of the roof collapsed during the fire.

Smith said the cause of the fire is unknown at this time and is under investigation.