First-responding police officers got four tenants of apartments above Firematic Safety Equipment out before part of a roof and stairwell collapsed in the two-story River Drive building shortly after 4:30 a.m., Police Capt. Richard Uram said.
Firefighters battling the intense blaze from the exterior needed about an hour and a half to get the bulk of it knocked down. They had it under control another hour and a half later.
No serious injuries were reported, Uram said, although a police officer required medical attention for a slip and fall.
The Red Cross was helping the displaced residents with food and shelter, Uram said. Garfield Community Affairs supplied jackets and other clothing, he said.
Fire Official James Kovacs said investigators were trying to determine the cause.
Mutual aid responders either at the scene or in coverage included firefighters from Clifton, Elmwood Park, Maywood, Moonachie, Rochelle Park, Saddle Brook, Teaneck and Wallington.
Firematic has provided extinguisher recharging, sprinkler inspecting and safety consulting since 1949.
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