We have learned the fire started in Schneider Distributing's main office.
Police Lieutenant Mike Hernandez says the large fire began at 4:46 a.m. at 403 MLK Boulevard.
Power lines are damaged, but no other surrounding structures were involved.
The city's public information officer Anthony Wilson says Schneider Distributing's office is "a total loss."
There were no injuries reported.
Wilson says one ladder truck, a rescue unit, three engines and an ambulance responded to the scene.
The San Angelo Fire Department has cleared the scene, but the city's Fire Marshal remains at Schneider Distributing, investigating the cause of the fire.
This is a breaking news story. We will continue to update the website as more information becomes available.