A fire at 99 Pleasant St. in Franklin, a multi-family home, displaced four residents.
A fire at 99 Pleasant St. in Franklin, a multi-family home, displaced four residents. Credit: JAY HEATH

Fire officials are investigating a four-alarm fire that displaced four residents and caused significant damage to a multi-family home Sunday afternoon in Franklin.

Three firefighters were transported to the hospital for treatment of heat-related injuries. Two of them, including a Franklin firefighter, were treated and released, while one remains hospitalized for observation, Franklin Deputy Fire Chief David Hall said by phone Monday morning.

The fire was reported at the three-unit residence at 99 Pleasant St. on Sunday at about 2:36 p.m. The call was quickly upgraded to a second alarm as flames were visible throughout most of the building, Hall said.

“Once the fire got into the structure, it extended up into multiple roof spaces and required extensive overhaul,” he said.

Nearly two hours after the initial call, firefighters declared the blaze under control at about 4:22 p.m. However, crews remained on scene until about 10:30 that evening.

Firefighters from 18 towns and cities responded to Pleasant Street. The Concord Fire Department was among the communities that provided mutual aid, and city firefighters checked for any occupants on the building’s third floor and helped fight the blaze in the attic.

The cause of the fire remains under investigation by Franklin Fire Department and the New Hampshire Fire Marshal’s Office.

The American Red Cross of Northern New England responded Sunday and is assisting residents displaced by the fire.