McALESTER, Oklahoma - Oklahoma has executed a 36-year-old man convicted of first-degree murder in the October 2000 stabbing deaths of a couple.

James Lewis DeRosa was killed by lethal injection Tuesday evening at the Oklahoma State Penitentiary in McAlester. His time of death was 6:07 p.m. and he was the second inmate executed in Oklahoma this year.

DeRosa had worked at the Le Flore County ranch owned by the victims, Curtis and Gloria Plummer. Prosecutors say DeRosa and an accomplice, 33-year-old John Eric Castleberry, slashed the Plummers' throats and made off with $73 and the couple's pickup truck, which was found abandoned at a nearby lake. The Plummers were in their 70s.

Castleberry pleaded guilty to first-degree murder and testified against DeRosa in exchange for a sentence of life without parole.