One firefighter was injured and needed help getting out of a burning house on Andrews Avenue in Naugatuck.
Crews said the blaze happened at a two-family home. Responding firefighters saw heavy smoke coming from the second floor and attic.
A firefighter hurt his leg and needed assistance getting downstairs and out of the house, according to crews. He was taken to Waterbury Hospital for treatment.
Five people living in the home were able to self-evacuate before crews got to the scene. No one else was injured.
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At least five people that were living in the home are receiving assistance from the Red Cross.
Multiple fire departments in the area provided mutual aid, including Beacon Falls and Waterbury.
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The fire department isn't sure what caused the fire and they're investigating.
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