COEUR d’ALENE — The Idaho State Fire Marshal’s Office said Thursday that grease accumulation was the cause of the Labor Day fire that destroyed the Wolf Lodge Steakhouse.

"It was determined that a breach in the flue pipe above the kitchen’s wood-fired grill allowed an accumulation of grease to form on the flue piping and inside the attic. This build-up of grease ignited and spread to the remainder of the building," a press release said. "The fire was classified as accidental."

Jason Blubaum, state deputy fire marshal, was one of the investigators of the scene the day after the blaze.

The fire was reported to 911 by a passerby at 11:58 a.m., who happened to be an Idaho deputy fire marshal, the release said.

"The deputy discovered staff on the roof of the building attempting to extinguish the fire with a garden hose. Fortunately, the deputy and the employees immediately began evacuating the inn, which was accomplished prior to the arrival of fire units," the release said. "Their quick action resulted in saving patrons’ lives."

Investigators from the State Fire Marshal’s Office, Kootenai County Fire and Rescue, and Bureau of Alcohol, Tobacco, Firearms, and Explosives arrived the following day to investigate. 

Thanks to the observations made by the deputy and other interviews, an area of interest was quickly identified, the release said.

"It was determined that a breach in the flue pipe above the kitchen’s wood-fired grill allowed an accumulation of grease to form on the flue piping and inside the attic. This build-up of grease ignited and spread to the remainder of the building. The fire was classified as accidental," the release said.