An Alabama prison captain and a former officer were arrested Monday on bribery and ethics charges, the state prison system confirmed.

The Alabama Department of Corrections said Capt. Deaundra Johnson and Centauria Olds, a former prison lieutenant, were arrested Monday on charges of bribery of a public servant and using their official positions for personal gain. Investigators also executed a search warrant as part of an ongoing investigation, the prison system said in a statement.

The prison system did not provide details of the accusations and court records were not immediately available. Olds was arrested last year on an accusation of accepting money from an inmate in exchange for bringing contraband into the prison, according to court records. The case was sent to grand jury, but it’s unclear if that led to Monday’s arrest.

“The ADOC is committed to enforcing its zero-tolerance policy on contraband, particularly when it comes to policing our own,” Alabama Corrections Commissioner John Hamm said in a statement. The prison system’s law enforcement division led the investigation.

An email to an attorney who had represented Olds was not immediately returned. It was not immediately known if Johnson has an attorney to speak on her behalf.

Johnson works at the Childersburg Community Work Center. She was placed on mandatory leave pending the outcome of the investigation.