Evan Ebel, the man suspected of killing the head of the Colorado prison system, threatened to kill a prison guard in September 2005 while he was incarcerated, according to records released Thursday by the Colorado Department of Corrections.
Ebel said he would make the guard "beg for her life" if he ever saw her on the streets, records indicate. He also was involved in two fights and three cases of assault and was written up for 28 violations during his imprisonment, the reports said.
The 28-year-old was on parole when he was mortally wounded in Texas on March 21 in a gunbattle with authorities that left a sheriff's deputy wounded.
Prison system chief Tom Clements was shot to death at his home outside Colorado Springs on March 19 and authorities have said the bullets that killed Clements came from a gun that was found with Ebel.
CNN's Carma Hassan contributed to this report.