Fire Commissioner Daniel Nigro says they received a call at 1:40 a.m. from a person across the street from the seven-story Fred Samuels Houses on Seventh Avenue near 142 Street reporting the blaze.
Nigro says firefighters responded within three minutes to the fifth-floor fire.
He says firefighters aggressively moved in to extinguish the flames and when they reached two rear bedrooms they found two adults and four children, ranging in ages from 3 to 11, deceased. They are all believed to be family members.
Nigro says there were approximately 100 firefighters on the scene and it took more than an hour to get the fire under control.