LAS VEGAS (KLAS) — A substance that a correctional officer was exposed to inside a Nevada prison remains a mystery.

It was initially believed to be fentanyl. Testing was done and hazmat was involved, according to a Nevada Department of Corrections spokesman. However, the substance remains unknown.

The 8 News Now Investigators obtained an internal memo signed by Jeremy Bean, the acting warden of High Desert State Prison.

While doing a cell search on Jan. 4, an officer was exposed to a substance that placed the officer in serious medical distress, according to the memo. Narcan was administered, the officer was taken to the nearest medical facility and was doing fine and recovering at home, the memo stated.

The memo refers to immediate changes, including additional Narcan inside the prison. Narcan is a medication that reverses an opioid overdose and can save the individual’s life when administered.

“HDSP has requested and received additional Narcan from the Division of Health and Human Services (DHHS) which will be distributed to each housing unit for emergency use purposes,” Bean wrote.

The memo also states that any staff member searching an inmate’s cell or handling an inmate’s property must wear latex/nitrile gloves and an N95 mask.

Bean also recognized staff members.

“First, I would like to thank all staff that participated in this response as your quick thinking and reaction saved the life of one of our own,” he wrote.

James Dzurenda returned as the director of the Department of Corrections on Monday. He told the 8 News Now Investigators that he plans to address the issue of drugs getting inside prisons, and this includes discussions about scanning personal mail entering the institutions.