Former Billings Clinic nurse Donald Mills– fired last year for diverting painkillers intended for patients for his personal use– has indicated he will plead guilty in U.S. District Court in Billings.

Mills is charged with tampering with consumer products and acquiring Fentanyl by misrepresentation, fraud, forgery and deception. Mills said he will plead guilty to the charges without a plea agreement. Fentanyl is a highly addictive synthetic opioid that is often fatal in high doses.