Officials say the fire happened at a home on Derby Avenue where 8-10 people were evacuated. There were no injuries reported and the Red Cross is on the scene.
When crews arrived on scene they saw the fire on the first and second floor. It was a difficult fight due to the intensity of the fire.
Derby called in help from Shelton and Ansonia.
Derby Avenue will be shut down for about another half hour before officials clear out of there.
The fire is under control, and the scene is being investigated.