One child was killed and more than a dozen other people were injured in southwest Michigan on Saturday after a suspected carbon monoxide leak in the indoor pool of a hotel in Niles.

Staff members at the Quality Inn & Suites found several children unconscious, lying on the deck Saturday, according to a local report.

First responders rushed the children to local hospitals; some of the rescuers were overcome by the noxious gas in the attempt, South Bend, Indiana NBC-affiliate WNDU reported. Carbon monoxide readings in the hotel’s enclosed pool area were 16 times higher than normal levels, the fire department told the news station.

Authorities have not released the name of the child who died Saturday afternoon.

Heidi Prescott, a spokeswoman for Beacon Health system, told The Washington Post that eight children had been brought to Memorial Hospital, along with one law enforcement officer. Six other patients — including the child who died — were taken to nearby Lakeland Hospital, said spokeswoman Megan Yore.

The Sheriff’s office and the fire department didn’t immediately provide details about the incident. Prescott said the hospital could not provide the names or ages of the victims.

Each year, more than 400 Americans die of carbon monoxide poisoning and another 20,000 visit the emergency room, according to the CDC.

A USA Today investigation of carbon monoxide poisonings at hotels found that between 2010 and 2012 the gas led to the death of eight people and sickened more than 170 people. The report also said that hotels rarely had carbon monoxide alarms.

In 2013, Daryl and Shirley Jenkins died at a Best Western in Boone, N.C. Six weeks later 11-year-old Jeffrey Williams died in the same room, according to an investigation by the Charlotte Observer. The cause of death was a carbon monoxide leak in the heating system for the swimming pool, just below the room where the deaths occurred.

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