The fire broke out on West 238th Street in Van Courtlandt Village just after 3 a.m.
Citizen App showed the flames bursting out of the building's windows.
The fire started on the fifth floor of the six-story building.
It took more than 100 firefighters about an hour and a half to get the fire under control.
The injured residents were rushed to Harlem Hospital and NY Presbyterian Hospital.
The cause of the fire is under investigation.
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