Authorities said that nine people were taken to hospital after they fell unconscious or experienced dizziness in the pool area.

Officials said that seven people were admitted to critical condition on Saturday following carbon monoxide poisoning at the Hampton Inn in Ohio.

According to The Columbus Dispatch, nine people were taken to the local hospitals. Marysville Fire Chief Jay Riley stated that although the source of carbon monoxide is unknown, all those who were hospitalized were in the hotel’s swimming pool.

Riley stated that the victims were both children and adults. Riley did not give exact ages.

Police said that they received a 911 call on Saturday night about a 2-year old girl who was either unconscious or had fallen into the pool. Tony Brooks, Marysville Police Chief, said that more 911 calls were soon received about unconscious persons or other symptoms like dizziness and burning in the throat.

Shortly thereafter, the hotel was evacuated. Brooks stated to the newspaper that all the injured were alive at the time they were taken and that seven patients were in critical condition.

Brooks stated that two others were treated on the spot, while five additional patients sought treatment at a hospital.

Late Saturday, the Dispatch was unable to reach the hotel’s management. Riley stated that a Hampton Inn maintenance crew was on its way from out of the state.

Marysville lies approximately 30 miles (48 km) northwest of Columbus.