Virginia ? A Virginia inmate who warned prosecutors he would kill again if not given the death penalty for strangling his cellmate was involved in the death of another inmate, authorities said.

Wise County Commonwealth’s Attorney Ron Elkins confirmed late Saturday that Robert Gleason Jr. was “involved” in the death of 26-year-old Aaron Alexander Cooper, though Elkins refused to elaborate. Gleason, who was already serving a life term for murder before killing his cellmate last year, has not been charged in the death.

Cooper died Wednesday in the recreation yard for inmates housed in segregation at the maximum security Red Onion State Prison in southwestern Virginia.