NATO said an airstrike in northern Afghanistan killed about a dozen insurgents, but President Hamid Karzai said the victims were campaign workers seeking votes in this month's parliamentary elections.
NATO said its airstrike on a car in northern Takhar province's normally quiet Rustaq district killed or wounded as many as 12 insurgents on Thursday, including a Taliban commander and a local head of an allied insurgent group, the Islamic Movement of Uzbekistan, responsible for attacks in Kabul and elsewhere.
However Karzai — who repeatedly warns that civilian casualties undermine anti-insurgency efforts — said the airstrike had killed 10 campaign workers instead.
"The rationale for the airstrike still needs to be fully investigated," the president said at a joint news conference in Kabul with U.S. Defense Secretary Robert Gates.
Gates said he had not heard about civilian casualties, but said the attack had hit its intended target and promised an investigation.
"I am able to confirm that a very senior official of the Islamic Movement of Uzbekistan was the target and was killed," Gates said.
Earlier, Takhar Gov. Abdul Jabar Taqwa said the car in which candidate Abdul Wahid Khorasani had been riding was fired on by helicopters following an initial pass by fighter jets. He called the incident an obvious mistake, saying there were no Uzbek militants, foreigners or members of the Islamic Movement of Uzbekistan in the convoy.
"There aren't even any Taliban in this area," Taqwa said. "They were all working on Mr. Khorasani's campaign."
Reached by phone at a hospital in Kabul, Khorasani said windows of the six vehicles in the convoy had been plastered with his campaign posters and all those traveling with him had been members of his extended family, including a man named Amanullah, who had been allied with a local Uzbek warlord and recently returned from a lengthy visit to neighboring Pakistan.
Khorasani said Amanullah had been among the 10 people killed in the attack, which he said also left seven wounded.
Khorasani, who said he received minor injuries, suggested the attack may have been prompted by false information fed to the Americans by a political rival, and called for a thorough investigation.
"I ask the international community and the Afghan government — investigate and find out who was the spy who gave you this bad information," he said.
A local politician with knowledge of the incident, but who declined to be identified due to the sensitivity of the matter, said the attack was likely linked to rivalries among ethnic Uzbek politicians in the province.
Afghan politicians have in the past been accused of deliberately feeding false information to foreign forces in hopes of prompting attacks and eliminating rivals. Political violence is on the rise ahead of the Sept. 18 polls, with at least three candidates and five campaign workers killed.
An alliance spokesman said it was aware of the claims that civilians were killed and would conduct a thorough investigation.
"What I can say is these vehicles were nowhere near a populated area and we're confident this strike hit only the targeted vehicle after days of tracking the occupants' activity," said Maj. Gen. David Garza, the deputy chief of staff for joint operations in Afghanistan.
Another NATO spokesman said the vehicle hit had stopped at least twice prior to the attack, during which men armed with rifles were observed exiting it before re-entering.
"We stand by the information in the release, and it is important to note that there was considerable time spent watching and waiting prior to the engagement," James Judge said.
Also Thursday, two American troops died in fighting, while NATO and local officials said coalition and Afghan forces killed dozens of insurgents in a series of ground and air engagements.
NATO said one U.S. service member was killed in the country's east and the other in the south — regions where fighting between the coalition and Taliban insurgents has been at its most intense. No other details were given in keeping with standard NATO procedure.
The deaths bring to three the number of U.S. service members killed in September and follow a spike in casualties during the last two weeks of August.