It happened at Olympic Panel, which is on Front Street in downtown Shelton.
The blaze started in one of rooms in the center of the building around 5 p.m.
The plant makes wood panels, and one of the motors that dry and glue the panels together ignited into flames. Witnesses said at the height of the incident they saw a big fireball light up the sky.
“There was a plume of smoke coming out of one of the buildings and it all broke loose. We had three different fire district in here and ambulance aid units,” resident Shawn Greenhalgh said.
The Central Mason Fire Department says the sprinkler system helped a lot and they were able to extinguish the blaze quickly. The damage is estimated at less than $10,000.