MARYSVILLE, Ohio (WCMH) – Sixteen people, including at least six children, were injured after reports of people being found unconscious in the pool area of a Marysville hotel Saturday evening due to what fire officials said was a high level of carbon monoxide.

According to Marysville Police Chief Tony Brooks, the calls started to come in at approximately 5:30 p.m., starting with a 2-year-old girl losing consciousness at the Hampton Inn on Square Drive. Dispatchers then received several more calls reporting people passing out.

Brooks said fire department investigators said there was a life-threatening level of carbon monoxide in the pool area, causing people to become unconscious.

Brooks said “multiple” people were affected in the incident.

According to Memorial Hospital spokesperson, seven patients were taken to the hospital by ambulance and four people were walk-ins. Of the 11 patients at the hospital, five were adults and six were children.

The spokesperson said two patients were critical but stabilized, five patients were in serious but stable condition, and four patients were treated and released.

Sunday morning, the spokesperson updated that the affected patients were transferred to tertiary care facilities to continue their recovery.

Three other people were taken to Grady Hospital, and two others were treated at the scene.

Brooks said people reported symptoms of a burning throat and dizziness.

“We really didn’t know what we were getting into,” Marysville Fire Department Chief Jay Riley said. “We thought we had just one child that was unresponsive in the pool, from there we had other victims identify themselves. So, we ramped up our response, we had additional medic units respond, and then also had our hazardous materials team respond.”

Officials have not said what caused the high carbon monoxide levels.

The hotel is privately owned and operated by the Amerilodge Group out of Michigan, which said it is cooperating fully with local authorities, who expect the hotel to be able to safely reopen in the next day or two.

This story will be updated as more information becomes available.