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US soldier accused in Afghan massacre had brain injury history

U.S. Army officials are preparing charges as new information is revealed about U.S. staff sergeant who allegedly shot 16 Afghan civilians. NBC Chief Pentagon Correspondent Jim Miklaszewski reports.

The American soldier accused of massacring 16 civilians in southern Afghanistan on Sunday was a 38-year-old staff sergeant based in Washington State who had no history of behavioral problems, but had been treated for traumatic brain injury after a previous deployment to Iraq, senior U.S. defense officials told NBC News.

The soldier, reportedly married with two children, enlisted in the Army soon after the terror attacks of Sept. 11 and did three combat tours to Iraq before arriving in Kandahar in December 2011.

The soldier was from the 2nd Battallion, 3rd Infantry Regiment of the 3rd Stryker brigade, 2nd Infrantry Division based out of Joint Base Lewis McChord located south of Seattle. He was among 2,500 soldiers sent to Afghanistan for a yearlong deployment.

He received his assignment to a village stabilization program less than six weeks ago, the defense officials said.

The attacker left his base in Panjwai district early on Sunday and broke into the homes of local villagers, according to reports. Nine children and three women were among the 16 slain. Some of the bodies were also reportedly set on fire. The BBC reported that the soldier was thought to have suffered a breakdown.

Afghan President Hamid Karzai called it an "assassination" and furiously demanded an explanation from Washington.

"This is an assassination, an intentional killing of innocent civilians and cannot be forgiven," Karzai said in a statement. He said he has repeatedly demanded the U.S. stop killing Afghan civilians.

President Barack Obama called the attack "tragic and shocking" and offered his condolences to the families of those killed. In a statement released by the White House, he vowed "to get the facts as quickly as possible and to hold accountable anyone responsible."   

U.S. and NATO officials were anxious to make clear that the shooter was acting alone.

"This was not part of a night raid or any operation," the senior officer told The New York Times. "All the signs point to a lone person acting alone."

MSNBC military analyst Gen. Barry McCaffrey (Ret.) says the alleged shooting of Afghan civilians by a US soldier is a 'further unraveling' of relations between the US and Afghanistan.

Nevertheless, some residents said they believed there were multiple attackers, given the carnage.

"One man can't kill so many people. There must have been many people involved," Bacha Agha of Balandi village told the AP. "If the  government says this is just one person's act we will not accept it."

Taliban vows 'revenge' after US soldier kills 16 civilans in Afghanistan

The staff sergeant accused of killing the Afghan civilians was treated for traumatic brain injury in 2010 after his vehicle rolled over in an accident that was not caused by an IED explosion, according to a senior U.S. defense official. He was medicated for some time, the official said.

The soldier was given a clean bill of health and received both pre- and post-deployment health assessments which did not indicate any problems, according to the defense official.

Officials said it was premature to state whether there was any link between the 2010 injury and the Afghanistan incident.

Home to about 100,000 military and civilian personnel, Joint Base Lewis McChord  has suffered a spate of suicides among soldiers back from war. The Army is investigating whether doctors at Lewis-McChord's Madigan Army Medical Center were urged to consider the cost of providing benefits when reviewing diagnoses of post-traumatic stress disorder.

Military discipline and the 'command climate' in Afghanistan comes into question after a U.S. soldier allegedly opened fire on sleeping civilians in Kandahar province. NBC's Jim Miklaszewski reports.

In 2010, a dozen soldiers from the base were arrested on a slew of charges that ranged from using drugs, beating up a whistleblower in their unit, and deliberately killing three Afghan civilians during patrols in Kandahar Province. Prosecutors at Lewis-McChord won convictions against four of the five who were charged in the killings.

Suspect's base has history of controversies

While U.S. officials rushed to draw a line between the shooting over the weekend and ongoing efforts of a U.S. force of around 90,000, the incident is sure to infuriate Afghans already suspicious of a Western military presence now over a decade old.

Jim Miklaszewski, NBC News chief Pentagon correspondent, said the recent incidents involving U.S. servicemen in Afghanistan raised questions about what the military calls the "command climate."

"Are the leaders there becoming a little slack perhaps in their discipline or enforcement of the rules?" he said on MSNBC. "U.S. military officials insist that this is not the case, but ... has the discipline eroded as forces prepare to withdraw?"

Last month, the burning of copies of the Quran on a NATO military base triggered violent protests across the country and a spate of insider attacks against Western soldiers.

US gives up control of jail where Quran was burned

In a statement Monday, the Afghan Taliban pledged to "take revenge" against the "sick-minded American savages," according to the AFP news agency.

"The American 'terrorists' want to come up with an excuse for the perpetrator of this inhumane crime by claiming that this immoral culprit was mentally ill," the Taliban statement added. "If the perpetrators of this massacre were in fact mentally ill then this testifies to yet another moral transgression by the American military, because they are arming lunatics in Afghanistan who turn their weapons against the defenseless Afghans without giving a second thought."

"This is a fatal hammer blow on the U.S. military mission in Afghanistan. Whatever sliver of trust and credibility we might have had following the burnings of the Quran is now gone," said David Cortright, the director of policy studies at Notre Dame's Kroc Institute for International Peace Studies and an advocate for a quick withdrawal from Afghanistan.

"This may have been the act of a lone, deranged soldier. But the people of Afghanistan will see it for what it was, a wanton massacre of innocent civilians," Cortright said.  

The soldier's name has not been released. He  is now in pretrial confinement as Army officials review his complete deployment and medical history.

The village stability operations are part of NATO's efforts to transition out of Afghanistan. They pair special operations troops with local villagers chosen by village elders to become essentially a sanctioned, armed neighborhood watch. 

NBC's Jim Miklaszewski and Courtney Kube, msnbc.com staff, Reuters and The Associated Press contributed to this report.

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