A Department of Public Safety trooper responding to the report of the shooting. (Photo by Rachel Cox)
Fort Hood, TX (CBS) - Investigators are focusing on the service and medical history of the Fort Hood shooter, who, according to CBS News sources, is Army Spc. Ivan Lopez, 34. Military officials have not confirmed that name, saying the soldier's family had not been notified.
Army officials say they believe this attack is not terror-related. The Army said the soldier was suffering from behavioral and mental issues, CBS News homeland security correspondent Bob Orr reports. He was being treated for depression and anxiety.
Lopez served in Iraq for four months in 2011. As far as sources know, he was not injured or wounded in action, but when he came home he told his military superiors he had suffered a traumatic brain injury, so he was being evaluated for post-traumatic stress disorder.
Sources say a preliminary check of Lopez's background has revealed no significant criminal record, and a search of the criminal and terror databases has turned up no evidence, so far, that he was connected to any kind of terrorist group, but nothing has been ruled out.
Investigators say the soldier used a .45-caliber semi-automatic pistol, which was purchased recently, in the attack. Federal officials are now working to trace the weapon and any recent purchases of ammunition he may have made.
As for motive, Orr reported this appears to be an incident of what's called soldier-on-soldier violence. It is not clear yet if Lopez was targeting specific soldiers or if the attack was random.
The shootings took place at a medical facility and a nearby command building - areas on the base that were familiar to Lopez..
Investigators are now going through his background. They're talking to family, friends and fellow soldiers. And they're also looking at Lopez's emails, phone records and computer files in an effort to determine if he left any clues or evidence of pre-planning.
Investigators want to identify any possible stressor - something that may have caused Lopez recently to snap and then react with violence.
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