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.
On Lopez's Facebook page, he has posted photos of himself in uniform and also posing with various weapons used in the Army. To view the photos on your mobile device, click here.