Mahdi, 42, chose to die by three bullets to the heart instead of lethal injection or the electric chair. COLUMBIA, S.C. — A firing squad on Friday executed a South Carolina man who killed an off-duty police officer, the second time the rare execution method has been used by the state in the past five weeks. Mikal Mahdi cried out as the shots hit him, and his arms flexed. He groaned two more times about 45 seconds after that. His breaths continued for about 80 seconds before he appear led to take one final gasp. A doctor checked him for...