The fire started around 3:35 p.m., Wednesday, March 13, at 24 Suncrest Road, said Norwalk Fire Department Deputy Chief Todd Smith.
According to Smith, firefighters arriving on the scene reported heavy fire in the rear of the building with an extension inside the building.
The initial engine company stretched the tagline through the structure to the rear and proceeded to extinguish the exterior fire which had by this time extended up the structures vinyl siding and into the structure itself including through the soffits into the attic, he added.
Additional arriving companies found heavy black smoke coming from all windows front and rear soffits in the eaves of the residence.
Two units were deemed unfit for occupancy and the tenants were relocated by the Norwalk Housing Authority, Smith said.
There were no reported injuries.
The Norwalk Fire Marshal Division is investigating the cause of the fire.
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