The fire broke out on the fifth floor of the apartment building on Linden Boulevard in Prospect Lefferts Gardens just before 2 a.m.
A 12-year-old boy and 69-year-old man died in the fire.
An 82-year-old woman and a 30-year-old woman were rushed to NYC Health & Hospitals/Kings County, where the 82-year-old female remains in critical condition and the 30-year-old female remains in stable condition.
Video from Citizen App showed fire shooting out of the building's windows.
The flames took about an hour to put out. The fire is under investigation.
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