• This undated photo shows Louisiana death row inmate Jessie Hoffman Jr., who was convicted in the 1996 murder of Mary "Molly" Elliott. (AP)

A death row inmate in the US state of Louisiana was executed on Tuesday using nitrogen inhalation, a method previously employed only in neighboring Alabama and condemned by UN experts as a form of torture.

The execution of 46-year-old Jessie Hoffman, convicted of kidnapping, raping, and murdering Mary "Molly" Elliot in 1996, marked Louisiana’s first execution in 15 years.  

Hoffman’s lawyers announced his execution through statements published by local media, though state authorities did not immediately confirm it.

"The State was able to execute him by pushing out a new protocol and setting execution dates to prevent careful judicial review and shrouding the process in secrecy," said Cecelia Kappel, one of Hoffman's attorneys.  

Three additional executions are scheduled in the United States this week, with one in Arizona set for Wednesday and two more in Florida and Oklahoma on Thursday. All three will be carried out via lethal injection.  

Since the start of the year, six executions have taken place in the US, all by lethal injection except for one by nitrogen inhalation in Alabama and another by firing squad in South Carolina.  

Hoffman’s legal team had appealed for a stay of execution to the Supreme Court, but their efforts were unsuccessful.

The world’s first execution by nitrogen inhalation occurred on January 25, 2024, in Alabama with the execution of Kenneth Smith, sparking widespread condemnation. Three more executions have since been carried out in the state.  

The death penalty has been abolished in 23 of the 50 US states, while six others—Arizona, California, Ohio, Oregon, Pennsylvania, and Tennessee—have imposed moratoriums on executions.