BURNHAM (CBS) — A spectacular fire in south suburban Burnham left 12 families homeless Monday morning.

The extra-alarm fire started around 3 a.m. at Southpoint Condominiums at 145th Street and Muskegon Avenue in Burnham.

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It burned fast and fierce, with flames leaping from the windows and roof for hours.

“It started in the front, but then it quickly spread into the back, and then across the whole roof,” said neighbor Trina Anthony.

As thick smoke blanketed the 12 units inside the building, alarms sounded, and residents began banging on doors, and calling to one another to get out fast.

“I just wanted to make sure everyone in the building was okay. That’s all I cared about,” resident Bernice Bryant said.

Frank Moore said thick smoke hit him in the face as soon as he opened the front door to his apartment to try to get out.

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“I closed the door back real quick, because I didn’t know if there was a fire out there or not,” he said. “They said get on the ground and crawl, so I had to crawl down the hallway from my unit to the stairs.”

No one was injured in the blaze, but the building was a total loss, leaving 12 families displaced.

At its height, the massive fire reached three alarms, requiring assistance from four neighboring communities.

“Anything that goes up to a three alarm is difficult, that’s for sure,” Burnham Fire Chief Andrew Horberg said. “There was heavy fire and smoke coming out of the building when the first companies arrived.”

Resident Carolyn Hughes said she heard someone banging on her door, but ignored it at first.

“If there’s a next time, I won’t ignore the knock,” she said.

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There were some reports that water pressure issues might have impacted how swiftly crews could battle the blaze. That’s under investigation, as well as the cause of the blaze.