Byron Black, 69, was executed Tuesday despite warnings that his defibrillator could cause pain. Witnesses say he cried out, “It’s hurting so bad.”

Byron Black is scheduled to be given a lethal injection after a legal battle about whether a working defibrillator in his chest would cause him pain.

The convicted murderer was put to death despite a legal battle over concerns his heart device would repeatedly shock him once the lethal chemicals spread throughout his body.