The fire was reported at 47 Riverside Ave. at 12:58 p.m. Thursday, according to Deputy Fire Chief Ed Prescott.
Firefighters arrived on the scene to find heavy fire on the first floor and extending into the second floor of the three-story home. Firefighters gained entry through the first floor and through a rear door on the second floor and began fighting the fire. It was quickly knocked down, and by 1:30 p.m. it had been extinguished, he said.
"There was a power line connected to the house that hampered us. CL&P responded right away and shut off power," Prescott said.
Five of the six residents were in the house when the fire started, Prescott said, but they left quickly.
Residents in the neighboring houses were evacuated, but the fire did not spread to any other structures. Nobody was injured in the incident, and the Red Cross arrived to assist the residents.
Fire marshals arrived on the scene and began investigating. The fire is believed to have started in the first-floor living room, Prescott said, but said it was too early to determine what caused it.
The entire city responded to the fire, Prescott said. Firefighters from Westport and New Canaan assisted by manning the Norwalk fire stations while the Riverside Avenue fire was still ongoing.
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