Transcript for The details of the California bar gunman
Investigators identifying the gunman today, Ian David long, who appears to have taken his life after taking so many others here. Here's ABC's chief justice correspondent Pierre Thomas tonight. Reporter: The FBI descended today on the home of the suspect, 28-year-old Ian long, a former marine machine gunner who saw combat in Afghanistan. These images posted to his mother's Facebook page show him in uniform. Other images posted to Facebook show him in happier times, smiling with friends. But tonight, evidence of a troubled man, and that critical question, were warning signs missed? Neighbors describing fits of anger at the home he lived in with his mother. The walls are kicked in and, you know, he was just -- couldn't control him. Reporter: Police today confirming they responded to a disturbance at that home in April, just seven months ago. He was somewhat irate. Acting a little irrationally. Felt he might be suffering from PTSD, basing that on the fact that he was a veteran. Reporter: They say mental health specialists cleared him after the incident. And because he was not involuntarily committed, he was not prohibited from buying firearms. Authorities today saying he legally purchased that Glock .45-caliber pistol allegedly used in the attack. Pierre Thomas with us live tonight. And as you reported there, the gun was purchased legally, but authorities say he allegedly used an extended magazine, which is illegal here in California? Reporter: That's right, David. Long did allegedly use an extended magazine in his gun, illegal in California, allowing him to fire more than ten bullets at a time. And we're now learning that gun was purchased in 2016.
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