Alabama inmate becomes first in US to be executed with nitrogen gas

Alabama on Thursday became the first state to execute a death row inmate using nitrogen gas.

Kenneth Smith was put to death by nitrogen hypoxia at the William C. Holman Correctional Facility in Atmore, Ala., making his execution the first in the U.S. to be carried out using the previously untested method.

Smith was executed for his role in the murder-for-hire plot of Elizabeth Sennett in 1988.

Alabama Department of Corrections Commissioner John Hamm addressed reporters during a press conference later Thursday night, noting that the state began carrying out the execution at 7:53 p.m. CST. Smith was pronounced deceased at 8:25 p.m. CST.