Inexperienced operators of a U.S. drone aircraft ignored or downplayed signs that Afghan civilians were in a convoy blasted in a deadly American missile attack earlier this year, a military report released Saturday said.
At least 23 people were killed in the Feb. 21 attack in Uruzgan province, deepening tensions between the Afghan government and NATO forces over the toll of civilian deaths at the hands of foreign troops.
It drew a strong rebuke from Afghan President Hamid Karzai and a quick apology from the commander of U.S. and NATO forces in Afghanistan, Gen. Stanley McChrystal, who is struggling to establish broad support among Afghans that is crucial to winning the almost 9-year-old war against the Taliban.
The insurgents claimed a victory Saturday when they captured a government outpost in Nuristan, a remote mountainous region near the Pakistan border.
Provincial governor Jamaludin Badar said government forces withdrew from the headquarters of the Bargi Matal district early Saturday after a major assault by Taliban militants and a battle lasting several days.
Taliban spokesman Zabiullah Mujahid claimed in a phone message sent to reporters that insurgents had taken complete control of the district, captured three police vehicles and forced security forces to flee road checkpoints.
Separately, NATO said the Taliban's "shadow governor" of central Baghlan province was killed in an airstrike on Friday, and that coalition forces had captured a Taliban commander in southern Kandahar province, an insurgent stronghold. NATO did not name either of the Taliban leaders, but it accused them of organizing attacks on coalition forces.
In the civilian deaths case, attack helicopters fired missiles and rockets into the convoy on a main road near Khod village, where U.S. Special Forces and Afghan troops were battling militants at the time, a summary of the investigation said. Commanders judged that the convoy contained fighters heading toward the village to reinforce the militants.
But the order to attack was based on inaccurate information from the crew at an Air Force base in Nevada that was remotely controlling a Predator drone monitoring the convoy and on flawed analysis of the situation by NATO commanders, Army Maj. Gen. Timothy McHale, who led the investigation, wrote in the report.
Poorly functioning command posts "failed to provide the ground force commander with the evidence and analysis that the vehicles were not a hostile threat and the inaccurate and unprofessional reporting of the Predator crew ... deprived the ground force commander of vital information," McHale wrote.
"Information that the convoy was anything other than an attacking force was ignored or downplayed by the Predator crew," it said.
In a memo released Saturday accompanying the report, McChrystal said he had issued letters reprimanding four senior and two junior officers in Afghanistan over the attack. He also called on the Air Force to investigate the actions of the Predator crew.
The report said the convoy drew early suspicion because men in it appeared to be providing security as it was tracked for more than three hours. Its movements matched radio intercepts of militants calling on others to join the battle near Khod, about seven miles (12 kilometers) from the site of the attack.
No women were seen in the vehicles, but two children were spotted near them at one point. This was inaccurately reported by the drone crew, the report said.
After the initial salvo, the helicopter crews stopped firing because they spotted brightly colored clothing amid the convoy -- a strong clue that women were present. Then, video shot from the drone showed women and children present.
McHale criticized the operation's commanders for failing to report the "ample evidence" of civilian casualties for nearly 12 hours after the attack, while they tried for confirmation.
U.S. forces spokesman Navy Rear Admiral Gregory Smith said the only people in the convoy that the drone crew could see were in the back of a pickup truck. Others were in closed cars. Smith said the Predator crew should have reported the possibility of civilians in those cars.
"They did not report the ambiguity of what they were seeing," Smith said. "They weren't clearly seeing a heavily armed threat."
Airstrikes accounted for about 60 percent of the nearly 600 civilians killed by NATO and Afghan forces in 2009, according to the United Nations. That percentage is significantly lower than the previous year, the U.N. said, attributing the drop to NATO directives to only conduct airstrikes as a last resort or if they are certain there are no civilians present.
"Our most important mission here is to protect the Afghan people," McChrystal said in a statement Saturday. "Inadvertently killing or injuring civilians is heartbreaking and undermines their trust and confidence in our mission. We will do all we can to regain that trust."
Human rights activists welcomed the report as a sign that NATO was being more open about admitting mistakes.
"But transparency and public accountability for the conduct of troops are still the exception rather than the rule," said Erica Gaston, a lawyer who works on civilian casualties issues for the New York-based Open Society Institute.
Unmanned aircraft are widely used in Afghanistan although they do not attract the attention here that they do across the border in Pakistan, where they have been used to attack extremist sanctuaries in the uncontrolled tribal areas. Those attacks have created huge outrage in Pakistan because of reports of large numbers of civilian deaths, as well as among insurgent leaders.
Associated Press writers Heidi Vogt and Rahim Faiez in Kabul contributed to this report.