An official report released Thursday finds that Oklahoma prison staff attempting to execute inmate Clayton Lockett in April failed to realize that lethal drugs were not going directly into his vein, leading to a botched execution and gruesome death that stirred a national debate over capital punishment.
Prison officials initially concluded that Lockett died of a heart attack, but an autopsy conducted in connection with the probe ordered by Oklahoma Gov.Mary Fallin found that he died from the lethal drugs.
At one point during the ordeal, Lockett appeared to struggle against his restraints. He was pronounced dead 43 minutes after the execution began even though the execution had officially been halted.
Lockett's was the first of two executions scheduled for April 29. The second was postponed after Fallin ordered the investigation into the case.