The fire started in a home on Summer Street around 1:30 a.m. and quickly spread to three others, each with several apartments inside.
A captain and a battalion chief were both taken to the hospital with injuries, while three other firefighters were treated at the scene for heat exhaustion.
"It really is very stewy out here, and it's taken down our firefighters," Paterson fire Chief Brian McDermott said. "So they are working hard, I just want to make sure they are all safe."
The fire went to so many alarms because of the heat and humidity. Of the four homes involved, three were completely destroyed.
Residents said they didn't hear any fire alarms going off.
"I was asleep, I smelled smoke, I got up," said fire victim Charles Harris, who lived on the first floor of one of the homes. "I looked up the back stairs and stuff, and I saw fire."
Some neighbors were woken up by frantic knocks by Yerisa Hernandez.
"As soon as I came out of the alleyway, I felt the heat already," she said. "I was like, 'Oh my God,' and I started waking up the neighbors, saying, 'You gotta get up, there's a fire, you gotta get out.'"
The Red Cross is at the scene assisting 13 families and 51 total residents.
"I don't even know where I should return to," Harris said.
The cause of the fire is under investigation.
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