Chattanooga firefighters battled a commercial fire that broke out about 9 p.m. Thursday at Zeco Inc., 4146 South Creek Road, just off Amnicola Highway.
Several firetrucks clustered at the scene. Police officers blocked off all roads in the area, and the smoke was visible from the highway.
No injuries were reported and the building was empty when the fire started, said Bruce Garner, fire department spokesman.
One witness reported hearing a boom and seeing a fireball.
Firefighters will be investigating the cause of the fire.