Louisiana executed a man convicted of murder with nitrogen gas on Tuesday evening, capping a raging legal battle that ended with a gas mask strapped over the man's face in the Angola State Penitentiary death chamber.

Louisiana used nitrogen gas to put Jessie Hoffman Jr., 46, to death Tuesday evening in the state's first execution in 15 years. Nitrogen gas has been used just four other times to execute a person in the United States — all in Alabama, the only other state with a protocol for the method.