In a historic event, Alabama carried out the nation's first known execution using nitrogen hypoxia on Thursday, as inmate Kenneth Smith was put to death. Now, Alabama Attorney General Steve Marshall is offering his assistance to other states interested in adopting this new form of capital punishment.

Smith, who was sentenced to death for his involvement in a 1988 murder-for-hire case, had previously survived a failed attempt of lethal injection in 2022. Despite his attorneys' efforts to prevent the execution, the US Supreme Court denied their final appeal on Thursday.

Critics, including Smith's legal team, experts, and advocates from the US to the United Nations, expressed concerns about the potential pain and the possibility of torture associated with the use of nitrogen hypoxia. However, Attorney General Marshall declared that the execution of Smith was "textbook" and a proof of its efficacy.

Currently, Alabama, Oklahoma, and Mississippi are the only three states that have approved the use of nitrogen hypoxia as a method of execution. Alabama is also the first state to have carried out such an execution and outlined a protocol for the procedure.

Following the successful execution of Smith, Attorney General Marshall expressed his belief that other states will follow suit. He stated, "Alabama has done it, and now so can you," while reassuring his colleagues across the country that Alabama stands ready to assist in implementing the nitrogen hypoxia method.

During Smith's execution, he was fitted with a mask that administered nitrogen, replacing the oxygen in his body. The process started at 7:53 p.m. CT and Smith was pronounced dead at 8:25 p.m., lasting approximately 15 minutes. Media witnesses reported that Smith appeared conscious initially, shaking and writhing, followed by deep breathing until his breath eventually became imperceptible.

Alabama Department of Corrections officials explained that the voluntary movement and agonal breathing observed during the execution were expected side effects of nitrogen hypoxia. Agonal breathing is an irregular gasping breath pattern that can occur near death.

Smith's spiritual adviser, Rev. Jeff Hood, who had previously expressed concern about the method, described the execution as "the most horrible thing I've ever seen," witnessing Smith convulsing, gasping, and heaving.

Smith made a lengthy statement before the execution, expressing love, peace, and gratitude towards his supporters. He even made a sign in sign language to his family in the witnessing room.

The exact time it took for Smith to die remains unclear, as the duration varies in lethal injections depending on various factors. Proponents argue that nitrogen hypoxia is a painless method, referencing its use in industrial accidents and suicides. Nevertheless, skeptics have expressed concerns about the potential for mishaps and the lack of transparency in the state's plan.

As the debate over the humane nature of this new execution method continues, Alabama is paving the way for other states considering the adoption of nitrogen hypoxia. With Alabama's Attorney General offering assistance, the future of capital punishment in the United States may undergo significant changes.

Note: The generated text has been edited for clarity and coherence.