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HILL DISTRICT (KDKA) — A firefighter wound up in the hospital Saturday night after fighting a fire at a Hill District apartment building.

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It happened at a 4-story building in the 3300 block of Iowa Street.

Pittsburgh Fire Chief Darryl Jones told KDKA that a piece of burning material fell down the back of the firefighter’s coat. He was taken to Mercy Hospital but should be OK.

Nearly 20 people, including 10 kids, will spend the night at a nearby church as firefighters investigate the cause of the fire.

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Neighbors say the flames broke out just after 8 p.m., and the fire quickly spread along the roof line.

“It was intense, and I could feel the heat standing on my porch,” neighbor Jennifer Perez said.

Craig Howell said he was fixing a car down the street when he spotted the flames. He ran inside the building and began yelling and banging on doors. He was happy to hear that everyone made it out safe.

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“I’m relieved. I didn’t want to go to bed tonight until I knew everyone was OK,” said Howell.