A late-night fire heavily damaged the old Plum Creek sawmill in Columbia Falls on Wednesday morning.

“It was going pretty good,” said Columbia Falls Fire Chief Rick Hagen when firefighters arrived about 12:30 a.m.

Crews had been tearing out old equipment using torches, Hagen noted. They had a fire watch on the scene until about 9:30 p.m., but the fire apparently started after the individual left. Hagen said when firefighters arrived, the old sawmill lunch room area was fully involved, with flames shooting out of the front of the building.

The old mill is part of the Columbia Rising industrial park and was purchased by private investors from Weyerhaeuser, which sold the site after it merged with Plum Creek. The fire was not at the new SmartLam facility, which is in the old planer plant.

Firefighters from Evergreen, Bad Rock and Whitefish all responded with mutual aid, as did Three Rivers Ambulance and Columbia Falls Police.

Firefighters were on the scene about four hours. No one was injured.

Hagen said the difficult part was putting out all the hot spots in the large building, which still had a significant amount of sawdust. He said it was challenging because there were holes in the floor from equipment being taken out.