Executed child killer 'showed signs of life' two minutes after his 'death'

A convicted child killer executed in Tennessee showed signs of "sustained cardiac activity" two minutes after he was pronounced dead, his lawyer has claimed.

Byron Black, who shot dead his girlfriend Angela Clay and her two daughters, aged six and nine, in a jealous rage in 1988, was executed in August by a lethal injection. Alleged issues about his case were raised on Friday as part of a lawsuit challenging the US state's lethal injection policies, amid claims they violate both federal and state constitutional bans on cruel and unusual punishment.

The latest proceedings in Nashville were held to consider whether attorneys representing death row inmates in the lawsuit will be allowed to depose key people involved in carrying out executions in Tennessee. The court heard that concerns had been raised before the execution that Black was being put to death with a working defibrillator implanted in his chest.

There were fears that the device would shock his heart when the lethal chemicals took effect. The Death Penalty Information Center, which provides data on such matters, said it was unaware of any similar cases.

Seven media witnesses said Black appeared to be in discomfort during the execution. He looked around the room as the execution began, and could be heard sighing and breathing heavily, the AP news agency reported at the time.

An electrocardiogram monitoring his heart recorded cardiac activity after he was pronounced dead, his lawyer Kelley Henry told a judge on Friday. Read more from Sky News:Executed man took at least 15 minutes to dieUS ramps up 'drug boats' operation Ms Henry, who is leading a group of federal public defenders representing death row inmates in the US state, said only the people who were there would be able to answer the question of what went wrong during Black's execution.

"At one point, the blanket was pulled down to expose the IV," she told the court. "Why? Did the IV come out? Is that the reason that Mr Black exclaimed 'it's hurting so bad'? Is the EKG (electrocardiogram) correct?" A full trial in the case is scheduled to be heard in April..