BALANDI, Afghanistan — Moving from house to house, a U.S. Army sergeant opened fire Sunday on Afghan villagers as they slept, killing 16 people — mostly women and children — in an attack that reignited fury at the U.S. presence following a wave of deadly protests over Americans burning Qurans.
The attack threatened the deepest breach yet in U.S.-Afghan relations, raising questions both in Washington and Kabul about why American troops are still fighting in Afghanistan after 10 years of conflict and the killing of Osama bin Laden.
The killing spree, the worst atrocity committed by U.S. forces during the Afghan war, comes amid deepening public outrage spurred by last month's Quran burnings and an earlier video purportedly showing American Marines urinating on dead Taliban militants.
The Quran burnings sparked weeks of violent protests and attacks that left some 30 Afghans dead, despite an apology from President Barack Obama. Six U.S. service members were also killed by their fellow Afghan soldiers, although the tensions had just started to calm down.
Residents said Sunday's attack began around 3 a.m. in two villages in Panjwai district, a rural region outside Kandahar that is the cradle of the Taliban and where coalition forces have fought for control for years. The villages are about 500 yards from a U.S. base in a region that was the focus of Obama's military surge strategy in the south starting in 2009.
Villagers described cowering in fear as gunshots rang out as a soldier stalked house after house firing on those inside. They said he entered three homes in all and set fire to some of the bodies. Eleven of the dead were from a single family, and nine of the victims were children.
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," said Bacha Agha of Balandi village. "If the government says this is just one person's act we will not accept it. ... After killing those people they also burned the bodies."
But U.S. officials said the shooter, identified as an Army staff sergeant, acted alone, leaving his base in southern Afghanistan and opening fire on sleeping families in two villages. Initial reports indicated he returned to the base after the shooting and turned himself in. He was in custody at a NATO base in Afghanistan.
The suspect, from Joint Base Lewis-McChord, Washington state, was assigned to support a special operations unit of either Green Berets or Navy SEALs engaged in a village stability operation, said a U.S. official, speaking on condition of anonymity because the investigation is still ongoing.
Such operations are among NATO's best hopes for transitioning out of Afghanistan, pairing special operations troops with villagers chosen by village elders to become essentially a sanctioned, armed neighborhood watch.
In a statement, Afghan President Hamid Karzai left open the possibility of more than one shooter. He initially spoke of a single U.S. gunman, then referred to "American forces" entering houses. The statement quoted a 15-year-old survivor named Rafiullah, who was shot in the leg, as telling Karzai in a phone call that "soldiers" broke into his house, woke up his family and began shooting them.
"This is an assassination, an intentional killing of innocent civilians and cannot be forgiven," Karzai said.