One man was rushed to a hospital in critical condition and another treated for less severe injuries Wednesday evening after a work accident caused an explosion and fire at a local diesel mechanic shop.

Shortly after 5 p.m. on Wednesday, April 10, emergency medical technicians and firefighters responded to a blaze at S&M Diesel, located at 3585 W. 5000 North, in an unincorporated area of Box Elder County between Bear River City and Honeyville.

Box Elder County Fire Marshal Corey Barton said an employee was using a plasma cutter on a metal storage tank when he accidentally hit an active fuel line. The employee who was using the cutter sustained severe burns in the explosion, but no additional details regarding his injuries or condition were available as of Thursday afternoon.

Barton said 25 firefighters from six agencies, including Box Elder County, Corinne, Fielding, Garland, Honeyville and Tremonton, responded to the resulting fire. He said the fire at the mechanic shop spread quickly and had already consumed much of the shop by the time firefighters were able to get there, but crews were able to extinguish the blaze before it spread to an adjacent home and other nearby structures.

“We were able to get it knocked down, but it took quite a while and there was quite a bit of damage,” Barton said. “It was quite an intense fire because of the fuel supply.”

Firefighters also faced the challenge of having a limited water supply from a nearby hydrant, so several “tender” trucks with large water tanks were brought in.

“They held it in check with what supply they had until the tenders got there,” Barton said.

He said the total damage to the facility is estimated at about $750,000.

“The building and everything in it is a total loss,” he said.

According to its website, S&M Diesel is a family-owned and operated company specializing in road service and towing. In addition to its Box Elder County location, the company also has a shop in Evanston, Wyo..