Investigators said the building is a total loss and there are fears what remains could collapse, CBS2's Kevin Rincon reported.
The fire at the Bristol Station apartment complex started around 2 p.m.
Firefighters from neighboring towns were on the scene throughout the afternoon to help get the rapidly spreading fire under control.
"She looked out the window and she just noticed there was lot of commotion and she saw the whole building was ablaze," said DJ Akinyemi, a neighbor.
"It started in the middle and then the back portion and then it just made its way down," another said.
Neighbors saw flames shooting out of a second floor balcony.
"It was, like, fire right here, and then, like, a gust of wind and it just went," neighbor Doug Reed said.
"Before we knew it, the fire had already gone up to the last floor and then it started to spread," said Samuel Odigi.
"I feel for these people, the tenants. It's so said," Angela Chandler said.
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The building had 48 units and 75 tenants.
"I stepped onto the balcony to water my plants, and I smelled, like, burning rubber," resident Mandeep Singh told CBS2's Nick Caloway.
Singh said it took at least five minutes for the alarms to sound.
"And when I walked inside my apartment to get my kids out, that's when the fire alarm started going off. And I knocked on my neighbors' [doors] and a couple other guys, and I just walked right out," he said.
By the time fire crews arrived, flames had reached the attic and spread the length of the building.
"These particular buildings, in the era they were built, did not have sprinklered attics. All of the apartments are sprinklered. All of the hallways are sprinklered, but not the attics. The fire goes up there and it moves unimpeded," said Fire Chief Mark Hruska.
Neighbors could only watch as crews doused the remaining hot spots.
"They probably put it out like four or five times and it just kept coming back," Reed said.
"It was so much smoke. It was just black. Like, it was crazy," said Bri Smith.
What wasn't gutted by flames was likely damaged or destroyed by smoke and water.
The Red Cross and Salvation Army came to assist the 48 families, some 75 people, who are displaced.
For many of them, reality is still setting in.
"That I lost everything in a matter of minutes. You know, everything I've worked hard for, and it's gone," resident Michelle Westervelt said.
All residents are accounted for, but some said they had pets inside.
They say firefighters wouldn't let them go inside to search for pets or personal belongings due to fears that the building might collapse.
"That I don't have a place to live anymore. That my animals are dead, and I have to take care of my wife, who has to experience this now," resident Jamie Tanner said.
"I have what I'm wearing, and that's it," Singh said.
Fire marshals are still looking for the cause of the fire. Officials on scene said the building could be torn down as early as Saturday morning.
Two firefighters suffered heat exhaustion battling the fire, but no other injuries were reported.
CBS2's Kevin Rincon and Nick Caloway contributed to this report. Editor's note: This story was first published Friday, July 23.
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