The second-alarm fire started on the second floor of a six-story apartment building at 1773 Vyse Ave. in the Crotona Park East section just after 4:30 p.m., and then extended to the floors above.
Officials say six people were injured, including four civilians -- two with serious injuries, and two with minor injuries -- and two firefighters who suffered minor injuries.
EMS took four civilians to St. Barnabas Hospital.
Over 45 units and more than 140 fire and EMS personnel responded.
NewsCopter 7 was over the scene where firefighters were battling the blaze. Smoke could be seen coming from several windows of the building.
The fire has not yet been placed under control, but officials said the main body of fire has been knocked down.
The cause is under investigation.
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