A metal warehouse caught fire early Monday morning.

According to the Knoxville Fire Department, units responded to Jim Sterchi Road shortly after 4 a.m. after a passerby called in to report smoke and loud explosions coming from the building.

When firefighters arrived, they found a single story metal warehouse-type structure with vehicles inside. Firefighters found flames and heavy black smoke created by flammable liquids, tires, and auto parts.

The fire department said the building was damaged by heat and smoke. No injuries were reported. The cause of the fire is unclear at this time.