The FDNY identified the victims as a 12-year-old boy, a 36-year-old man and a 40-year-old woman. It was not immediately known how they were related.
Four other people inside the three-story house suffered minor injuries in the early Monday morning blaze on Prospect Avenue in the Tremont section. Four firefighters also had minor injuries.
A fire chief at the scene told WCBS radio that firefighters encountered heavy flames shooting out of the building's front door.
A fire department spokesman said 106 firefighters responded to the scene of the 3:30 a.m. blaze. It was brought under control about one hour later.
The cause of the fire is under investigation.
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