Clayton Lockett: Oklahoma execution goes wrong
30 April 2014 Last updated at 13:14 BST
Prison officials in the US state of Oklahoma have halted an execution half way through, after botching the delivery of a new untested combination of drugs.
The prisoner, Clayton Lockett, was still said to be shaking uncontrollably 20 minutes after the first drug was administered. He later died of a heart attack.
Richard Lister reports.