By CBSNewYork Team

NEW YORK (CBSNewYork) — Five firefighters were hurt battling a large fire Monday in Coney Island.

The flames broke out just before 6 a.m. at a two-story commercial building on Mermaid Avenue.

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Fire officials said poor ventilation and heavy smoke made the fire extremely difficult to fight.

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No one was inside the building when first responders arrived, and it’s unclear how it started.

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The injured firefighters suffered heat-related injuries and were all expected to be OK.

CBSNewYork Team