BRADFORD, Maine — A fire destroyed a sawmill on Monday, but the cause is not known, Bradford Fire Chief Dusty Kelley said Monday night.

The fire was discovered about 1:30 p.m. by a passerby, who alerted the owner, Kelley said. He said that people who were at the mill at the time attempted to put the fire out with an extinguisher but that the wind picked up and the fire got away from them.

The sawmill operator had been cutting grade stakes about an hour before the fire started, the fire chief said.

Kelley said it was not clear how the fire began and that an investigator from the state fire marshal’s office was called in to help pinpoint the cause.

Crews from Bradford were assisted by firefighters from Corinth, Charleston, Hudson, Glenburn, Kenduskeag, Milo, LaGrange and Alton. Many of them remained at the scene as late as 7:30 p.m.

The sawmill on Storer Road belongs to Dwight Perkins, Kelley said. It was not insured, he said.

Bangor Daily News writer Ryan McLaughlin contributed to this report.