Guthrie said the call came at about 8:30 p.m., and the initial callers reported seeing smoke and flames coming from the building.
Crews arrived at the building shortly afterward, and Guthrie said he didn't know how long it took to get the blaze under control.
He said 10 companies from the counties of Campbell, Halifax and Charlotte all sent units to the scene.
Saturday afternoon, Guthrie said there were still multiple hot spots in the rubble, but that getting to all of them at one time would be difficult, not to mention dangerous.
"It's three floors piled down in the basement, so it's hard to get to," he said.
The milling company, he said, dealt mainly in feeds for farm animals.
Guthrie said crews were still keeping an eye on the rubble on Saturday.
No one was injured in the blaze, and Guthrie said the cause of the fire was not known Saturday afternoon.
Written by The News and Advance