Michael Blane Dowda, 48, is considered armed and dangerous, corrections spokeswoman Jasmine Cole said in a news release.
Visitation was closed Sunday. Calls to ask whether Dowda remained at large Sunday or whether visitation would resume Monday were not returned.
Cole said officials realized Saturday afternoon that Dowda was missing from a maintenance detail. He allegedly stole a white 2005 Silverado truck with Yalobusha County disability tag number 0922 and drove out.
When last seen, he was wearing the prison uniform: a white shirt and green-and-white-striped pants.
Dowda was sentenced for killing Clarissa Lynn Jarrett of Woolmarket at their home during an argument Nov. 13, 1996. He said he'd removed the clip and thought the gun was unloaded. Authorities said one bullet was still chambered.
He chose to be tried without a jury. A judge convicted him in 1998 of depraved heart murder — causing death by an obviously dangerous act.
Dowda is described as white, 5-foot-11 and 195 pounds, with brown eyes and brown hair and a tattoo on the left side of his chest.
According to court documents, Dowda apparently got a .380 semi-automatic handgun and drove home nonstop from a job in Orlando, Fla., after learning on Nov. 12, 1996, that Jarrett was going to a concert in Alabama with her sister.
He arrived early Nov. 13, 1996, confronting Jarrett when she arrived. He threatened to kill himself, then took the clip out of the gun, put the gun in a closet and continued the argument.
After Jarrett said she had had sex with other men, Dowda got the gun, put it to her head and pulled the trigger.
Copyright 2012 The Associated Press.