FLORENCE, Ariz. -- A transcript of an emergency court hearing reveals that Arizona officials assured a judge during the nearly two-hour execution of a U.S. inmate that he was comatose and not feeling pain at any point.

Joseph Rudolph Wood gasped for about 90 minutes during his execution on Wednesday. The process took so long that his lawyers had time to file an emergency appeal while it continued.

"He has been gasping and snorting for more than an hour," Wood's lawyers wrote, demanding that the courts stop the execution. "He is still alive."

The emergency hearing included a defence lawyer, an attorney for the state and a judge. They discussed Wood's brain activity and heart rate, questioned if he was feeling any pain and talked about whether it would do any good to stop the execution while it was so far along.

"In talking with the director, who has been in consultation with the IV team leader, there has been no appearance of any pain," a lawyer for the state said during the hearing.

Arizona Attorney General Tom Horne's office said Wood, 55, was pronounced dead at 3:49 p.m., one hour and 57 minutes after the execution started.

The third botched execution in six months in the U.S. has rekindled the national debate over the death penalty and given potentially new evidence to those building a case against lethal injection as cruel and unusual punishment.

In Ohio, an inmate gasped in similar fashion for nearly a half-hour. An Oklahoma inmate died of a heart attack, minutes after prison officials halted his execution because the drugs weren't being administered properly.

Arizona Gov. Jan Brewer said she was ordering a full review of the state's execution process, saying she's concerned by how long it took for the administered drug protocol to kill Wood.

An Associated Press reporter who witnessed the execution saw Wood start gasping shortly after a sedative and a pain killer were injected into his veins. He gasped more than 600 times over the next hour and a half. During the gasps, his jaw dropped and his chest expanded and contracted.

An administrator checked on Wood a half dozen times. His breathing slowed as a deacon said a prayer while holding a rosary. Wood finally stopped breathing and was pronounced dead 12 minutes later.

"Throughout this execution, I conferred and collaborated with our IV team members and was assured unequivocally that the inmate was comatose and never in pain or distress," said state Department of Corrections Director Charles Ryan.

Defence lawyer Dale Baich called it a botched execution that should have taken 10 minutes.

"Arizona appears to have joined several other states who have been responsible for an entirely preventable horror -- a bungled execution," Baich said. "The public should hold its officials responsible and demand to make this process more transparent."

Family members of Wood's victims in a double 1989 murder said they had no problems with the way the execution was carried out.

"This man conducted a horrific murder and you guys are going, let's worry about the drugs," said Richard Brown, the brother-in-law of Debbie Dietz, who was killed along with her father. "Why didn't they give him a bullet?"

Wood looked at the family members as he delivered his final words, saying he was thankful for Jesus Christ as his saviour. At one point, he smiled at them, which angered them.

Arizona uses the same drugs -- the sedative midazolam and painkiller hydromorphone -- that were used in the Ohio execution earlier this year. A different drug combination was used in the Oklahoma case.

"These procedures are unreliable and the consequences are horrific," said Megan McCracken, of the University of California, Berkeley, School of Law's Death Penalty Clinic.

States have refused to reveal details such as which pharmacies are supplying lethal injection drugs and who is administering them out of concerns that the drugmakers could be harassed. States have been scrambling to find potentially lethal drugs as several European-based pharmaceutical companies refuse to supply them if they are intended for executions.

Wood filed several appeals that were denied by the U.S. Supreme Court. Wood argued he and the public have a right to know details about the state's method for lethal injections, the qualifications of the executioner and who makes the drugs.

Such demands for greater transparency have become a new legal tactic in death penalty cases.

The 9th U.S. Circuit Court of Appeals had put the execution on hold, saying the state must reveal the information. But the Supreme Court has not been receptive to the tactic, ruling against death penalty lawyers on the argument each time it has been before justices.

The Arizona governor said medical and eyewitness accounts indicated that Wood did not suffer and he died in a lawful manner in which justice was served.

Attorney general's spokeswoman Stephanie Grisham, who witnessed the execution, said Wood "went to sleep, and looked to be snoring."

"This was my first execution, and I was surprised by how peaceful it was," Grisham said in an email. "There was absolutely no snorting or gasping for air."

Wood had been convicted of fatally shooting Dietz and her father, 55-year-old Gene Dietz, at their auto repair shop. Wood and Debbie Dietz had a tumultuous relationship during which he repeatedly assaulted her. She tried to end their relationship and got an order of protection against Wood.