The Air Force airman who shot two employees, one fatally, inside a Wal-Mart in Grand Forks and then took his own life was drunk at the time of the bloodshed, authorities said Wednesday.

Marcell Willis, 21, stationed at the Air Force base west of Grand Forks, had a blood alcohol content level of 0.19 percent when he drove to the store and entered about 1 a.m. on May 26, according to autopsy results. That level is more than twice the legal limit for driving in North Dakota.

The autopsy, performed at the University of North Dakota, also determined that Willis killed himself with a gunshot to the head.

Gregory Weiland, 70, was killed and Lisa Braun, 47, was injured in the shooting and is recovering. Willis shot at a third worker and missed. Weiland had worked for Wal-Mart for 24 years. Braun has worked at the store since September 2009.

Authorities have yet to say what a motive might have been in the shooting, which Willis carried out with his personal handgun and not a military-issued firearm. Police have said there appears to be no connection between Willis and the employees he targeted.

Two passengers were in the car that brought Willis to the store, but they did not know what was about to happen, according to Police Lt. Derik Zimmel. Willis made up a story about why he needed to stop there, and the two were “as clueless to his motives as anybody else,” Zimmel said.

Willis’ girlfriend, Amy Mehs, said on Facebook that the two were to be married in September.

Willis, who grew up in Springfield, Tenn., was a military cadet his senior year at Springfield High School, played on the football team in 2011 and sang in the choir. He had been stationed at the nearby Grand Forks Air Force Base since February 2013 and achieved the rank of senior airman.

Services for Willis were scheduled for Wednesday in his hometown.