US state's prison boss wants Oklahoma executions suspended

The director of prisons in Oklahoma wants an indefinite stop to all executions in the US state so procedures can be revised, after a botched lethal injection sparked allegations of torture.

Clayton Lockett, a convicted murderer and rapist, was left writhing in agony on Tuesday after he was administered a new, untested three-drug protocol in what would have been the central state's first double execution in 80 years.

He died 43 minutes after the start of the lethal injection of a massive heart attack. The process usually takes 10 minutes.

In a letter to Oklahoma Governor Mary Fallin, the state's Department of Corrections Director Robert Patton recommends a "comprehensive review of the execution protocol."

He said that would require a suspension of executions and recommended asking for court approval.

Patton revealed that, prior to his execution, a defiant Lockett had been tasered early on Tuesday and he had also deliberately cut his arm.

Patton also said that technicians had found it difficult to find a vein to insert the lethal drugs in and eventually found a "vital point" in the groin -- suggesting that "the drugs were injected into Mr. Lockett's flesh, rather than his veins," according to attorney Madeline Cohen.

Patton's recommendations include putting decision-making in more senior hands, he said, adding: "I intend to explore best practices from other states and ensure the Oklahoma protocol adopts proven standards."