Alleged Houston Shooter Was Veteran, Stepmother Says 'I Think He Was Haunted' by Time in Afghanistan

PHOTO: ABC station KTRK-TV reports that a source close to the investigation says that Dionisio Garza III is the gunman in a shooting that took place in Houston, May 29, 2016.PlayCourtesy of Dionisio Garza III's family
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The devastated stepmother of a military veteran identified as the alleged gunman behind a deadly shooting in west Houston told ABC News, "I think he was haunted by everything he experienced" in Afghanistan.

Houston police today identified the alleged gunman as Dionisio Garza, 25, of California, who died in Sunday's shooting. Police said it appeared Garza was in a "mental health crisis."

Garza's stepmother, Cathy Garza, told ABC News she thinks he might have had post-traumatic stress disorder.

"I think he was haunted by everything he experienced there. I think it changes you," she said. "I don't know how you can go through what he went through and see what he saw and not have it change you or affect you."

Garza's cousin, Ahmad Alkuteifani, told KTRK-TV today, "I don't think he was ever the same after he saw what he saw over there. I think it took a toll on him."

The Army confirmed to ABC News that Garza was deployed to Afghanistan twice between 2009 and 2013 and that he was discharged in 2014.

Alkuteifani told KTRK-TV that when Garza returned from his two tours of duty, he posted anti-Islamic comments on his Facebook page, even though some of his family, including Alkuteifani, are practicing Muslims.

The Sunday shooting spree, described as "random" by police, left one victim dead and six people injured. Houston police said today Garza shot a total of 212 rounds.

"We're devastated," Cathy Garza said. "I can't help but think of all the families that were affected by this."

Police said today the suspect had been living with his sister in California and drove to Houston, where he arrived Saturday.

He had allegedly "been suffering from depression," Houston Police Lt. John McGalin said today during a news conference. "His family indicated that he wasn’t feeling right and he left to come here and hang out with his friends and try to find work here."

Cathy Garza said the 25-year-old was kind, loving and respectful, and that nothing seemed out of the ordinary the last time she saw him.

"It just wasn't him," she said. "That's not who he was."

ABC News' Jim Vojtech contributed to this report.