MADISON — An electrical problem in an office at Backyard Farms sparked a fire Thursday that led to the evacuation of the tomato producer’s two large greenhouses, a fire official said.

A fire alarm activation shortly after 8 a.m. prompted a response by about 30 firefighters from several agencies, according to Madison fire Chief Don French.

First responders found flames and heavy smoke shooting from one of the buildings on the expansive grounds of Backyard Farms on River Road, northeast of downtown Madison. The building where the fire began houses several offices and is connected to one of the greenhouses, he said.

The fire moved into the roof but was quickly knocked down and French credited one Madison firefighter in particular, Geoff Holbrook, who was one of the first on scene and who attacked exterior flames before entering through a window to suppress flames inside as well.

“My guys made a heckuva knockdown to save a lot of structural damage,” French said.

No injuries were reported. French said the building where the fire started was heavily damaged and that smoke traveled into a packing area and also into the adjacent greenhouse. It’s not clear whether that smoke impacted the tomatoes being grown there and Backyard Farms did not respond to an email message seeking information.

A state fire investigator responded to the scene and made the preliminary determination that an electrical issue in one of the offices led to the fire, French said.

Joining Madison firefighters at the scene were others from Anson, Athens, Norridgewock, Skowhegan, Solon, Starks and Waterville, which provided a ladder truck. New Portland covered Madison’s fire station.

French expressed appreciation for the assistance from the other agencies, particularly in light of how many Madison firefighters have full-time jobs outside the immediate area that can at times slow their response.

Backyard Farms was founded in 2007 and is one of the largest employers in the region. It was bought by Mastronardi Produce Ltd. of Kingsville, Ontario, in 2017. Backyard Farms operates on 42 acres, featuring the two greenhouses.

Mastronardi Produce packs its specialty and commodity non-GMO greenhouse produce under the SUNSET brand.

In Madison, Backyard Farms’ greenhouses utilize hydroponics, meaning plants are grown in a water solution stocked with nutrients.

The business grows a variety of tomatoes, including beefsteak, cocktail and tomatoes on the vine, which are shipped to many stores, including Hannaford, Shaw’s, Walmart and Whole Foods.