(NBC News) Wednesday's second mass shooting at Fort Hood is shaking up Washington, and the Secretary of the Army has warned more attacks on other bases are possible.
The latest Fort Hood shooting, which left four dead and 16 wounded, came just months after an attack at the Washington Navy Yard. It follows the previous Fort Hood massacre, in which Major Nidal Hasan took 13 lives, by nearly five years.
Army Specialist Ivan Lopez, the gunman responsible for Wednesday's carnage, had sought treatment for mental illness prior to purchasing the handgun he wielded in the killings.
"There's no question that those with mental health issues should be prevented from owning weapons, or being able to purchase them," House Speaker John Boehner said in response.
But experts say identifying who among the many with mental issues might be dangerous is almost impossible.
Captain Pete Hegseth of Concerned Veterans for America says what is possible and needed more than ever is improving access to mental health care in the military
"It can't be a stigma, that you're not a tough guy if you come forward and seek help, because otherwise you're suppressing folks that might have a need," he says.
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