McALESTER — Proclaiming his innocence and saying he would see his victim in heaven, a man convicted of battering his girlfriend’s 8-year-old son and stuffing the body in an abandoned freezer was executed Thursday at the Oklahoma State Penitentiary .

Donald Lee Gilson, 48, lifted his head and smiled at his family before a lethal mix of drugs began to flow through his veins at 6:14 p.m. He was pronounced d...