PHOENIX -- An inmate at a prison near Florence, Ariz. died Monday after taking his own life, the Arizona Department of Corrections said in a press release.
Gregory Dickens, 48, was given lifesaving measures, but they failed.
Dickens was sentenced to death after being convicted of first-degree murder, armed robbery and conspiracy to commit armed robbery. He had been on death row since Dec. 17, 1993 and was serving his sentence at the Arizona Prison Complex - Eyman.
Dickens was convicted of robbing and killing a couple on Sept. 10, 1991 at a rest stop along Interstate 8 near Yuma, Ariz. The man gave details to authorities before dying.
DOC officials and the Pinal County Medical Examiner's Office are investigating Dickens' death.
The Associated Press contributed to this report.