The U.S. Army staff sergeant accused of massacring 16 Afghan villagers earlier this week was flown out of Afghanistan after 9 p.m. local time Wednesday, according to US and NATO officials.
The alleged shooter, whose name has not been released, was flown to Kuwait, a Defense official told ABC News.
A U.S. military official said that the suspect had been moved because of concerns for his safety inside Afghanistan and because of sensitivity to the host nation. Pentagon spokesman Capt. John Kirby said that the suspect has been moved to "an appropriate detention facility outside of Afghanistan," but would not identify the country.
"This is primarily because inside Afghanistan we don't have the proper detention facilities to detain US personnel for any length of time," said Kirby. "So this is in accordance with our own regulations and policies to have him in a proper detention facility where he can continue to be interviewed and to be cared for appropriately."
Officials say the soldier will be identified once military prosecutors file charges. The Army's Criminal Investigative Command is conducting the investigation into the shooting rampage and will forward their results to the military chain of command. Charges can be filed while the investigation continues.
Afghan political leaders have called for the shooter to be tried publicly in Afghan courts, but U.S. military officials say the case will be handled in U.S. military courts. A U.S. military official says Afghan officials were made aware of the transfer before it occurred.
Whether that trial takes place in Afghanistan or the United States remains to be seen.
The shooting occurred at 3 a.m. Sunday morning in three houses in two villages in the Panjway district of southern Kandahar province, an area that was once a Taliban safe haven but has recently become more safe after a surge of troops in 2009.
The alleged shooter has been identified as a 38-year-old Army staff sergeant based at Fort Lewis in Washington state.
He was assigned to Camp Belambay, a remote combat outpost where his job was to be protection for Special Operations Forces who were creating local militias. He was not a member of the special forces unit. He allegedly left the base in the middle of the night and wore night-vision goggles during his rampage, according to a source.
The first village was more than a mile south of the base. While there, he allegedly killed four people in the first house. In the second house, he allegedly killed 11 family members -- four girls, four boys and three adults.
He then walked back to another village past his base where he allegedly killed one more person, according to a member of the Afghan investigation team and ABC News' interviews with villagers.
All of the victims were shot in their homes, according to villagers and the Afghan president's office. Video from the scene show blood-splattered floors and walls inside a villager's home and blood-soaked bodies of victims, including the elderly and young children, wrapped in blankets and placed in the backseat of a van.
Some of the bodies appear to have been burned.
Pentagon spokesman Kirby said officials "don't know what his motivation was. We are looking into that."
The staff sergeant confessed to the crime when he returned to his base that night saying, "I did it," defense officials told ABC News.
According to the officials, the staff sergeant returned to his base in Kandahar where he was disarmed. Back at the base, said officials, he said, "I did it," and described the massacre. According to defense officials, villagers were already reporting the massacre before the suspect returned to the base.
The soldier has since retained a lawyer and is refusing to speak with investigators about what motivated him to allegedly gun down the civilians. Officials told ABC News the alleged shooter had been having marital problems since returning from deployment in Iraq in 2010 before he was sent to Afghanistan.
ABC News has learned that the soldier suffered a mild traumatic brain injury in 2010 while on deployment in Iraq.
It is unclear if the injury could have played a role in Sunday's massacre. An official told ABC News that the soldier has suffered a mild traumatic brain injury (TBI) in the past, either from hitting his head on the hatch of a vehicle or in a car accident. He went through the advanced TBI treatment at Fort Lewis and was deemed to be fine.
He also underwent mental health screening necessary to become a sniper and passed in 2008. He had routine behavioral health screening after that and was cleared, the official said.
When the soldier returned from his last deployment in Iraq he had difficulty reintegrating, including marital problems, the source told ABC News. But officials concluded that he had worked through those issues before deploying to Afghanistan.
Investigators are also looking at the possibility that alcohol may have played a role in the incident, defense officials said, as alcohol was found near where he lived on base in Afghanistan.
On Monday, the suspect appeared before a magistrate where probable cause for continued pre-trial confinement was established.