NEW YORK (CBSNewYork) — More than a dozen people were sent to the hospital Tuesday morning after a carbon monoxide leak in a Bronx apartment building.

Firefighters were called to the building on East 172nd Street when the first alarm went off at around 3 a.m. and turned off the boiler, but three hours later, carbon monoxide filled the building.

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“I heard running up and down the stairs and I knew some commotion was going on,” resident Lillian Rodriguez told CBS 2’s Kristin Thorne.

Rodriguez and her daughter, Genevieve Weiler, say they think someone in the building turned the boiler back on after it had been shut off by firefighters.

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“For someone to put it back on knowing that we weren’t supposed to, it’s a scary thing,” said Weiler.

In all, 18 people including five children were taken to Jacobi Medical Center and are expected to fine.

Con Ed turned off the gas line to the boiler so that a leak won’t happen again and residents are being kept out of the building until it is aired out. They’ll be without heat until the boiler is repaired.

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