WESTWOOD, Kan. (AP) — Law enforcement authorities say a Kansas prison inmate is charged with killing a man in 2003 in a suburban Kansas City grocery store.

Forty-year-old Eugene Clayton Keltner faces a first-degree murder charge in the death of David “Ray” Ninemire in Westwood. Ninemire was shot when he went to help a co-worker during a robbery at the grocery store.

Johnson County District Attorney Steve Howe on Thursday declined to say what evidence led to Keltner’s arrest. Keltner is imprisoned in Lansing after being convicted of involuntary manslaughter in a 2004 shooting death in Kansas City, Kansas.