Southwestern New Hampshire District Fire Mutual Aid reported the property as being at 218 Elliot St., though some at the scene said it was 214.
Fire departments from Brattleboro, Keene and Spofford, N.H., and others from around the region responded to the three-alarm blaze that forced authorities to close off a portion of Elliot Street. Firefighters were battling the inferno with multiple hoses, as black smoke visible from Western Avenue billowed into the air.
Dozens of people convened at the scene and took photographs and video footage of the fire.
Helen Mican said she lived in Apartment 3 and was sleeping on her couch when she heard the fire alarms and then someone banging on doors to inform people of the fire. She told the Reformer she grabbed her two cats and ran outside.
"It started in Apartment 5 - that's what they're saying," she said, adding that there are seven apartment units in the building. "They're still trying to contain the fire on the roof."
She said she moved into the building five or six weeks ago.
The Reformer will update this story later.