A former Cherry Point Marine will spend the next 40 years in a Virginia prison after pleading guilty to first degree murder.
Don Walker was a corporal at the air station when he was arrested for the December 2010 murder of his girlfriend's estranged husband in Montgomery County, Virginia.
Investigators say Walker broke into 25-year-old Matthew McPeak's Christiansburg home, turned off the power and ambushed the victim when he came home. McPeak was stabbed repeatedly with a hunting knife.
McPeak's wife, Danielle Vinese McPeak, received a 40-year sentence in May. She pleaded no contest to first-degree murder.
Investigators say Walker was having a long-distance relationship with Danielle McPeak and she plotted her husband's slaying.