The American soldier who allegedly went on a shooting spree in Afghanistan, killing 16 villagers as they slept, had a traumatic brain injury at one point in his life, officials told ABC News. The soldier had been declared fit for duty and was deployed to Afghanistan in December, but his identification remains under wraps as protests over what is to be done with him spread across the country. Reports on Monday were that the soldier was a 38-year-old who had been deployed four times, the first three in Iraq. An official said the soldier had suffered a mild traumatic brain injury in the past in a minor accident and had received treatment at a U.S. base. He had also undergone a mental-health screening to become a sniper in 2008. The soldier was said to have had marital problems during his last deployment in Iraq and had trouble reintegrating with his squadron.