Transcript for Who Was the Shooter at Fort Hood?
A lot of information coming out overnight about the shooter. ABC's Pierre Thomas has that part of our coverage. Good morning, Pierre. Reporter: Good morning, robin. The suspect was apparently suffering from serious mental health issues and sources tell me that likely played a key role in yesterday's tragic shooting spree. While the motive for the shooting is unclear, military officials are describing the suspect as a man in turmoil. Possibly suffering from posttraumatic stress disorder. He was undergoing behavioral health and psychiatric treatment for depression and anxiety. He was on medication. Reporter: Ivan Lopez had told officials he suffered from a traumatic brain injury but the military had not been able to confirm that. He was not a wounded warrior. He was not wounded in action to our records. No purple heart. Reporter: Lopez had served in Iraq for four months in 2011 and had only come to ft. Hood in February. His neighbor told us he had moved near the base just three weeks ago with whom she believes are his wife and daughter, a toddler. I noticed his wife coming out of the apartment and she was hysterical. Reporter: Authorities say Lopez bought the 45 caliber smith & Wesson handgun used in the shootings at a local gun store in recent days. Because he was not officially determined to be mentally ill by a court, the purchase was perfectly legal but the shooting on the heels of the 2009 mass murders at ft. Hood again raises questions about base security. If you have a weapon and you're on base it's supposed to be registered on base. We'll have to re-examine all those programs and see if there were any gaps. Reporter: Sources tell us they're investigating whether a dispute on or near the base may have started the mayhem. A key question this morning, did this man clearly suffering from mental health issues fall through the cracks and were there enough red flags to stop him from buying a gun?
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