ASHLAND, Ky. — A former inmate at the Martin County federal prison who was indicted last month for assaulting guards at the facility has now been charged with murder.

Daviian Dwane Roberts, 35, formerly of Midland, Texas, is now charged with murder for allegedly killing fellow inmate Michael Smith in October of 2024.

Last month, he was charged with three counts of assaulting USP Big Sandy correctional officers after being accused of attack three guards with a weapon in March of 2025.

The assault charges could add up to 20 years to Roberts’ sentence, but the murder charge could result in a sentence of any length, including life.

Roberts is currently being held in the federal supermax prison in Florence, Colo. No hearings have yet been set in either case.