Chillicothe, OH – Emergency crews are responding to the Ross Correctional Institution for a mass casualty incident after 20 employees and one inmate became suddenly ill.

The Ohio State Highway Patrol said they were notified at about 9 a.m. on Wednesday morning that 15 corrections officers, five nurses, and one inmate were being treated for possible drug overdoses, WCMH reported.

Ohio State Highway Patrol Public Affairs Officer Lieutenant Robert Sellers said the people who were exposed to the unknown substance have been given the overdose reversal drug naloxone, according to the Chillicothe Gazette.

Lt. Sellers said there were at least 300 doses of naloxone available at Ross Correction Institute should they be needed.

Extra doses of narcan were delivered to the prison as investigators worked to try to figure out what the substance was that had affected so many people, WCMH reported.

Ohio State troopers said the drug was possibly fentanyl, WCMH reported.

The opioid drug fentanyl is 50 times stronger than heroin and 100 times more potent that morphine.

Fentanyl can enter a person’s body through the lungs, skin, or eyes once the drug becomes airborne. WCMH reported that an overdose can be caused by as little as 2.3 milligrams of fentanyl.

Chillicothe Police responded to the scene to assist state police and prison authorities with the emergency situation, and at least five other departments have responded to assist those who were impacted by the mass casualty incident, according to the Chillicothe Gazette.

A mass casualty incident, by definition, occurs when the number and severity of casualties have overwhelmed emergency medical services resources, such as personnel and equipment.

Lt. Sellers said the prison planned to evacuate at least one housing unit, but that the prison is secure. A hazardous materials team has responded to the prison to assist with cleanup, he said.

Unioto Schools, which are located adjacent to the Ross Correctional Institute property, went into a cautionary lockdown due to their proximity, the Chillicothe Gazette reported.

Nearby, Adena Local Schools were operating as usual, although Superintendent John Balzer said they were closely monitoring the situation because the parents of a number of students were employed by the prison facility, according to WCMH.

Police have said there is no threat to the public, according to WMCH.

The Ross Correctional Institution is a men’s medium security prison located in Chillicothe. It houses about 2,000 inmates and has 494 staff members, WCMH reported.

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