Ironton Fire Capt. Craig Thomas said a fire in a silo containing 600 tons of sawdust at Muth Lumber is almost out now.

The blaze ignited Thursday afternoon just after 2:30 p.m. Thomas said there has been no determination yet as to what caused the sawdust to go up in smoke.

“It could be spontaneous combustion,” Thomas said. “We got a Bobcat from the city and we’re taking out bucket loads (of sawdust) and dropping it off to the side and keeping water on it. We thought we had it out last night and left about 10 o’clock but it flared up again.”

Thomas said putting out a fire in a silo full of sawdust is not an easy as it might sound. Sawdust, when sprayed with water, tends to cling to the side of the silo.

Firefighters remained on the scene as of press time.