An electrical malfunction is believed to have caused the fire that destroyed two large buildings and damaged several others at the Fryeburg Fairgrounds on Tuesday, a State Fire Marshal’s Office investigator said Wednesday.

Sgt. Ken Grimes, a fire investigation supervisor, said witness interviews led his team to the area where the blaze originated in an electrical subpanel next to a bank of light switches.

“There was extensive damage as you can imagine,” he said. “The building was down on the ground. We were able to locate an area of origin based on witness interviews. That pointed us in a direction, and we were able to establish the electrical malfunction once we located that area.”

Grimes said investigators were lucky that people were around preparing the area.

“It’s a benefit to us that they’re already working on the fairgrounds getting ready for the next season, so there was a lot of people for us to talk to,” Grimes said.

The blaze destroyed the two buildings and damaged six others. There were no injuries to people or animals.

The Fryeburg Fire Department was called about 7 p.m. and arrived to find a sheep barn engulfed in flames. The fire spread to an adjacent cattle shed, and both buildings were destroyed. Each one was 150 feet long and from 30 to 50 feet wide.

Chief Andrew Dufresne estimated the damage at about $500,000.

The fire was under control by 9 p.m. More than 20 departments helped contain the blaze. The East Conway (N.H.) Fire Department wrote on Facebook, “A quick response from many mutual aid departments and strong command got this incident under control quickly.”

The Fryeburg Fair is held annually in late September and early October, and the chief said he expects new structures will be built in time for this year’s fair.

Maine’s Blue Ribbon Class, the state’s largest agricultural fair, will run from Sept. 30 to Oct. 7 on the 200-acre property.

“It’s a very important place for the residents here, as well as visitors who come here,” Dufresne said. “It’s definitely a loss that hits close to the heart, but the good news is that no one was injured.”

Flames, fanned by strong winds, rip through a barn at the Fryeburg Fairgrounds on Main Street on Tuesday evening. A state fire investigator said the blaze started in an an electrical subpanel next to a bank of light switches. (East Conway Volunteer Fire Department photo)