Details continue to emerge about Mauricio Garcia, the Texas gunman who shot up a mall near Dallas over the weekend and killed eight people. Today (May 9), officials revealed that Garcia joined the U.S. Army 15 years ago, but was expelled after mental health concerns began to arise.

NBC News reported that Garcia entered basic training for the Army in Fort Benning, Georgia in June 2008. But soon after he arrived, Army officials were concerned about his mental health and said he also had an adjustment disorder as he struggled with stressful changes.

Garcia was 18 at the time and was training to become an infantry soldier. But he was discharged within three months and was removed prior to receiving rifle training, according to officials. Still, he never publicly communicated a threat or committed a crime, leading military personnel to believe at the time that they didn’t have to notify authorities about their concerns.

These details about his brief military stint come on the heels of the Army saying yesterday (May 8) that Garcia was “terminated” without completing basic training because of a physical or mental condition. “We do not provide characterization of discharge for any soldier,” Heather Hagan, an Army spokeswoman, said of the terms of his departure.

Federal and state officials spoke more about Garcia’s life and the lead-up to Saturday’s (May 6) deadly mass shooting in a news conference today. He had no criminal history and was able to legally purchase all eight firearms that were recovered at the scene. After the incident, in which he died, he was discovered to have been an avid neo-Nazi who espoused violent white supremacist rhetoric online.

Hank Sibley, a regional director at the Texas Department of Public Safety, informed citizens that investigators are looking into Garcia’s separation from the military and that information about his “fitness for duty” would eventually be made public. Sibley also noted that Garcia had been working as a licensed security guard for several firms prior to the attack but was not recently active.