Oklahoma unveils renovated execution chamber after botched execution of Clayton Lockett
Mug shots of convicted murderer and rapist Clayton Lockett (L) and convicted murderer and rapist Charles Warner [AFP]

Oklahoma prison officials on Thursday unveiled a renovated execution chamber inside the Oklahoma State Penitentiary, aimed at addressing issues that arose during the state's last execution.

The state made additions and improvements to the chamber in McAlester following the botched execution of condemned murderer Clayton Lockett in April, when an intravenous tube was placed incorrectly in his groin area, according to state officials.

Approximately $34,000 of the $106,000 spent on the project went to new medical equipment, including an ultrasound machine to help locate veins on the condemned, state prison officials said.

The "improvements ... will improve overall efficiency,” said Scott Crow, administrator of field operations at the Oklahoma Department of Corrections.

The execution chamber was also outfitted with an electronically controlled bed, restraint and intercom systems and an ECG machine, prison officials said.

New communications equipment and cameras were also added to the execution chamber, the adjacent operations room and the two witness areas, officials said.

Refrigerators designed to hold chemicals were placed in the operations room, which was also outfitted with monitoring stations and phone lines. Witness rooms were furnished with new chairs and carpeting, as well as one-way viewing glass, according to prison officials.

In addition to the improvements, the state has put in place new execution protocols, including increasing the dosage of a controversial sedative and allowing the corrections department director to choose from four lethal injection options.

Oklahoma postponed executions after Lockett's and has scheduled three executions in November and December.

(Editing by Brendan O'Brien and Eric Walsh)