Two St. Louis firefighters were injured Sunday when part of a burning building collapsed while they were battling the blaze in the 4100 block of Kennerly.

One firefighter was temporarily trapped.

St. Louis Fire Department spokesman Capt. Garon Mosby said one of the injured firefighters was treated at a local hospital and released Sunday morning.

The other injured firefighter was treated and didn’t need to be taken to the hospital. The firefighters were injured when a wall of a vacant home collapsed while they were checking whether anyone was inside. Mosby said it took great effort to lift the roof just enough to free the injured firefighter.

The cause of the fire has not been determined.