Forming part of a four-drug concoction, fentanyl was used as a painkiller. The other drugs included the sedative diazepam to render unconsciousness, the muscle relaxer cisatracurium to stop the prisoner's breathing and potassium chloride to stop the heart.
"I recognize that today's execution impacts many people on many levels," said Scott Frakes, director of the Nebraska Department of Correctional Services. The lethal injection was carried out with "professionalism, respect for the process and dignity for all involved," he added.
German company takes actionAuthorities have complained that ethical measures taken by pharmaceutical companies have made it harder to obtain drugs needed to carry out an execution.
German pharmaceutical company Fresenius Kabi last week challenged the inmate's execution, claiming that Nebraskan authorities had improperly acquired two of their drugs.
Read more: Fresenius case puts spotlight on misuse of medicines in executions
However, the state insisted it had legally acquired the drugs through a US-based pharmacy. Judges ruled in favor of the state, allowing the execution to go through.
'I am guilty'Carey Moore, the 60-year-old inmate executed on Tuesday, did not attempt to get a last-minute stay of the execution.
In his final words, he alluded to a written statement he made earlier this month, claiming that other death row inmates were innocent. "I am guilty, they are not," he wrote. "Why must they remain there one day longer?"
Read more: Death penalty: Pope Francis makes seismic shift in Catholic Church policy
In 2015, Nebraska's state legislature outlawed capital punishment. But a year later, Republican Governor Pete Ricketts pushed a referendum to have it reinstated. The referendum passed, effectively restoring capital punishment to the Midwestern state.
ls/rc (Reuters, AFP)
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