POST FALLS — The fire that ripped through a particleboard plant early Sunday caused more than $1 million worth of damage and is expected to shut down the employer of 75 people up to three months.

Kootenai County Fire and Rescue responded to the blaze at Plummer Forest Products, 401 N. Potlatch Road, at 4:52 a.m.

"This was quite a hit (to the business)," said KCFR Division Chief Steve Isaacson. "It's really tragic."

There were no injuries to employees or firefighters.

"There was excessive damage because we had a really big fire," Isaacson said. "A lot of that had to do with access issues. We had to cut holes in sidewalls and there were roof failures. When the fire spreads behind walls, it's difficult to identify and physically chase."

The fire was caused by a mechanical failure of the equipment.

"They're going to be working for the next two weeks around the clock cleaning up," Isaacson said. "It is expected to be closed for up to three months."

A message left for company officials wasn't returned as of deadline Monday night.

Fire crews have responded to fires at the business multiple times over the years. Wood products being transported on conveyors naturally make fires more likely at the company than at many businesses. Oftentimes, the company tends to small fires itself without needing to contact KCFR.

However, this incident was "radically different" than previous calls, Isaacson said.

"This was truly a building on fire," he said, adding that other incidents were contained to the conveyor system.

Isaacson said the fire department was thankful that the company has a quality sprinkler system. Otherwise, the damage would have been even worse.

"We were blessed that they had their own fire hydrants and water supply," he said. "The sprinklers began to flow immediately, which helped us keep the fire in check. Without their incredible fire suppression system, we would've had a really bad situation."

When crews arrived, the fire in the main milling building was spreading to adjoining structures and rooms.

Fire crews remained at the business until 3 p.m. Sunday to assure the blaze was completely extinguished.

Coeur d'Alene Fire and the Northern Lakes Fire District also responded to assist KCFR.

Potlatch built the particleboard plant in 1975 and operated it until 2010, when it was purchased by Plummer Forest Products. It was the first mill in North America to produce wood particleboard using a formaldehyde-free resin system. The company uses the EnStron (environmentally strong) brand for its product line.