MANSFIELD — “Several” Mansfield Correctional Institution staff members were affected by an unknown substance Saturday night, according to Scott Basquin, the prison’s public information officer.

“Some staff came in contact with an unidentified substance, and were taken to and released from the (OhioHealth) hospital,” Basquin said. “We can’t call it a drug because we don’t know what it was.”

The incident is under investigation by the Ohio State Police Department, he added.