Arizona execution took nearly two hours on Wednesday, and the prisoner's lawyers said he gasped and snorted for an hour.
The execution of Joseph Wood — which Arizona carried out with a lethal-injection it had never before tried — is certain to fan the debate over how U.S. states carry out the death penalty.
Midway through the execution, defense attorneys asked a judge to stop the execution of Joseph Wood and order prison officials to try to resuscitate him. But before the court acted, he was pronounced dead.
"The execution commenced at 1:52 p.m. at the Arizona State Prison Complex (ASPC) - Florence. He was pronounced dead at 3:49 p.m," a statement Arizona Attorney General Tom Horne said.
The statement did not say what problems the execution team had encountered, but Wood's lawyers painted a macabre picture.
"He has been gasping and snorting for more than an hour," lawyers wrote in their request for an emergency stay of execution.
"He has been gasping and snorting for more than an hour."'
Wood — who was condemned to die for fatally shooting his girlfriend and her father in 1989 — had challenged the execution on the grounds that the state was violating the First Amendment by keeping the source of the lethal-injection drugs secret.
An appeals panel agreed with him, but the U.S. Supreme Court lifted the stay of execution. The Arizona Supreme Court briefly delayed the execution on Wednesday morning, but ultimately gave the state the green light.
Wood, 55, was scheduled to be killed with a combination of midazolam and hydromorphone, the same drugs used in an Ohio execution in which the inmate seemed to struggle for air and took 25 minutes to die.
His execution date had been put on hold several times as the case wound its way through last-minute appeals. One of those decisions was notable for a dissent in which the chief judge of a federal appeals court said the guillotine would be better than lethal injection for executions.