Seventy people were displaced by the 10 School St. fire, which had struck multiple alarms as of 2:10 p.m., Passaic Mayor Hector Lora said.
Footage shared by Armando Marin shows the building beginning to collapse as flames rip through the roof and upper level.
Locals watched stunned, muttering expletives under their breath as the bricks of building 10 began to fall.
Buildings 8 and 12 were structurally compromised, the mayor said, noting everyone, including all pets, have been accounted for.
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