The blaze started around 6 a.m. inside the building on Watson Avenue in the Soundview section.
Video showed the flames shooting through the roof, and some 200 firefighters and EMS responded to the scene.
"On arrival, they found a fire on the top floor in what we call the cockloft space, which is the space between the ceiling and the roof," FDNY Chief of Operations Richard Thomas said. "Once it gets into the cockloft space, it spreads pretty quickly. So just trying to catch up and stay on top of it, and our members did an excellent job."
All of the injuries are believed to be minor.
"There was a lot of smoke and somebody was banging on the door telling everybody to get out," resident Delores Washington said. "But now we're trying to get back in, because we got our stuff inside."
The FDNY is investigating whether or not there were working smoke detectors in the building.
"Why didn't the alarm go off?" resident Demba Sanyang said. "The smoke alarm didn't go off, and the odor alarm didn't go off."
Another point of concern for neighbors who were also forced to evacuate is the fact that there was a similar fire in a similar building just across the street about a year and a half ago. That fire also started on the top floor.
Sixteen families, consisting of 130 residents, have been left temporarily homeless. An air conditioned bus was at the scene to offer relieve for the displaced, and by Friday afternoon, some residents were allowed back inside but only to retrieve some belongings.
The cause of the fire in 2017 was deemed to be electrical.
The cause of Friday morning's fire remains under investigation.
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