Two firefighters were reported with minor injuries, authorities said, adding that all residents apparently got out safely.
Flames tore through the roof of the Gregory Avenue building at the corner of Broadway after the fire broke out around 9 p.m.
Unofficial preliminary estimates were that 400 people from 60 apartments were displaced.
Nearly a dozen companies responded, including those from Carlstadt, East Rutherford, Rutherford, Pompton Lakes, Wanaque, Wallington and Wayne, while several remained on standby, including Hawthorne and Paterson, according to the Northern New Jersey All Incidents Facebook page.
"They were fighting the interior in patches and then switched to the exterior when it was getting too bad and the fire was coming through the roof," Rutherford Fire Chief Craig Scott told Daily Voice.
One of his firefighters sustained a knee injury, Scott said.
Rutherford Fire Lt. Brian Sartori saved a cat.
"We didn’t think anything would be alive in there," Scott said. "Someone from Passaic fire got a dog out, too."
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