MASON, Mich. (AP) — A Michigan sheriff says a former jail inmate will face charges that he gave the opioid-withdrawal medication methadone to another prisoner who died of a drug overdose in September.

The Ingham County sheriff says tests determined 39-year-old Mark Kelly Rhodus of Monroe died from multiple drug intoxication, including methadone and cocaine. Rhodus was found dead inside his jail cell on Sept. 12.

Sheriff Scott Wriggelsworth says only one other inmate in that cellblock had a prescription for methadone. Wriggelsworth said Wednesday that man was being sought for arrest on a charge of drug delivery causing death.

The sheriff said investigators didn't know how Rhodus obtained the other drugs. He had been jailed since Aug. 3 for parole violation.