LIBBY, Mont. - It took a mere three minutes to arrive on site Thursday night after the 911 call came in but Libby firefighters found the former Stimson Lumber Co., plywood plant fully engulfed in flames.

The 4.7-acre building burned to the ground and was still smoldering on Friday while a steady stream of vehicles passed by to see the destruction.

"The moon was shining out and the plume was so huge that it looked like someone dropped an atomic bomb," Lincoln County Sheriff Daryl Anderson said. "Embers were flying through the air all over."

Residents from neighboring homes were evacuated as Libby and Troy firefighters worked to contain the flames.

Phil Spencer and Joel Chandler watched helplessly as all of the equipment and inventory from their specialty business, Wedge Wood Products, went up in flames.

"It hadn't burnt yet but the fire department wasn't able to get water up to it because of the 2,400-volt line that was running next to the road there," Spencer said. "My partner begged the fire marshal to put water on it to save it, but the fire marshal said he couldn't because the line wasn't shut off."

Spencer estimates their loss at $250,000 on the uninsured business. In addition, the fire ate up about 10 unpatented machines that had taken Spencer 15 years to engineer. They had closed production in the winter to install new equipment and were ready to begin work on Monday.

"I feel a little bit wobbly from it all," he said. "March was going to be when we put people to work because we already had orders and the equipment and a good start on stock to produce."

The sheriff's office requested a state fire marshal to investigate.

"We have no idea where the point of origin is at this time," Anderson said. "It got so hot so fast. Apparently some people were working that day doing some welding and torching work. We don't know yet if it has anything to do with the fire."