Investigators say a gas leak inside a laundromat apparently sparked a five-alarm fire that injured nine firefighters and gutted a two-story building in Jersey City.

Fire Director Armando Roman tells The Jersey Journal that the laundromat's manager heard a loud noise around 5 p.m. Sunday and soon discovered a fire had broken out behind a dryer.

The blaze soon spread and eventually destroyed four businesses on the ground floor. It also displaced six to eight families who lived in apartments on the second floor.

It took nearly three hours to bring the blaze under control.

One firefighter was injured when he was knocked off the roof by some building materials that he and other firefighters were removing. Eight other firefighters also were treated for heat exhaustion.

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