More than 120 firefighters responded to the fierce four-alarm blaze, which roared across the multi-family dwellings on Oak Street after breaking out shortly after 8 a.m., responders said.
An off-duty firefighter helped get the buildings evacuated, Fire Chief Patrick Trentacost said
"There was a tremendous amount of fire through [two of ] the buildings, with a partial collapse," Trentacost said.
Everyone got out safely and no injuries were reported. Trentacost said the initial number was 35 residents but may be more.
"At least two of these structures will have to be taken down," Passaic Mayor Hector Carlos Lora said.
Mutual aid responders included firefighters from Carlstadt, Clifton, East Rutherford,Haledon, Little Falls, Paterson, Rutherford, Totowa and Wallington.
The cause wasn't immediately determined.
Oak Street remained closed between Main and Myrtle avenues.
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