"I didn't do anything to be in here," Miller said in his final words, the AP reported. His words were at times muffled by the blue-rimmed gas mask that covered his face from forehead to chin. Miller asked his family and friends to "take care" of someone, but it was not clear whose name he said.

Alan Eugene Miller, who was put to death on Thursday, was convicted of killing three people during a 1999 workplace shooting spree.

Alabama used nitrogen gas Thursday to execute a man convicted of killing three people in back-to-back workplace shootings, the second time the method that has generated debate about its humaneness has been used in the country Alan Eugene Miller,