One person was found dead and 13 others were hospitalized after a group of people were found unconscious around a hotel’s indoor pool in southern Michigan.
Fire officials said they believe the cause was carbon monoxide poisoning.
Thirteen people were treated at local hospitals, including hotel staff members and first responders who helped unconscious victims, according to police in Niles, Michigan, a town of about 11,000 just north of the state’s border with Indiana.
A spokeswoman for Lakeland Hospital in Niles told CNN that one person was “confirmed dead on arrival.”
Seven others were taken to Memorial South Bend Hospital in Indiana, Lakeland spokeswoman Jessica Hines said. Six were in stable condition, and one was in critical condition.
There were six people found unconscious around the pool at the Quality Inn & Suites hotel, and all of them children between 10 and 14 years old, Niles police said.
Police responded to the hotel around 10 a.m. ET, according to CNN affiliate WNDU-TV.
Police said that, when they arrived, carbon monoxide levels at the hotel were 800 parts per million, according to CNN affiliate WBND-TV. US standards for carbon monoxide are 35 parts per million for a one-hour exposure.
Carbon monoxide is an odorless, colorless and tasteless gas that is produced when a fuel is burned. When too much carbon monoxide is in the air, it can replace the oxygen in red blood cells and can lead to tissue damage or death.
Choice Hotels, which owns the Quality brand, released a statement about the incident, saying it is “working closely with local officials to manage the situation. … Our highest priority is always the safety and well-being of our guests.”