A Georgia man who was recently sentenced to death in the killings of two corrections officers during an escape attempt five years ago has died in prison of an apparent suicide, corrections officials said.

Prison guards found Ricky Dubose unresponsive in his cell at the Georgia Diagnostic and Classification Prison in Jackson around 4:45 p.m. Sunday, according to a Department of Corrections news release. The guards called for medical help and began rendering aid. The coroner at the prison declared Dubose dead at 5:56 p.m.