CHILLICOTHE, Ohio (AP/WJZ) –  Maryland Department of Public Safety and Correctional Services has temporarily suspended visits at corectional institutions statewide as precaution after staff and inmates at prisons in Ohio and Pennsylvania were sickened by illness and possible drug exposure.

The State Highway Patrol says more than 20 people have been treated for possible drug exposure at an Ohio prison.

READ MORE: 3 Baltimore Firefighters Killed In Partial Building Collapse, 1 In Critical Condition

“We are taking precautions to ensure the safety and security of our employees and inmates,” Dept. Secretary Stephen T. Moyer said

Steps being taken include no prison visits until further notice, mail will be accepted at facilities but not opened or distributed and staff has been advised to use all provided protective equipment.

Patrol spokesman Lt. Robert Sellers says 23 staff members at Ross Correctional Institution and one inmate began showing signs of a drug overdose Wednesday at 9 a.m.

READ MORE: Maryland Weather: Potential Nor'Easter Could Bring Snow This Weekend

Sellers says the inmate and staff members, including several guards and nurses, have been administered naloxone. The drug is used to combat overdoses caused by opioids such as heroin or fentanyl. The prison is about 44 miles (71 kilometers) south of Columbus.

Sellers says inmates in the unit where the exposure occurred were evacuated and a hazmat team will clear it. An investigation is ongoing.

Messages were left for the prisons system and the union representing correctional officers.

Follow @WJZ on Twitter and like WJZ-TV | CBS Baltimore on Facebook

MORE NEWS: Gun Stolen From Baltimore Used In Ambush Shooting of NYC Officers, Police Say

(© Copyright 2018 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)