Also Sunday, the bodies of 10 members of a medical team - six Americans, two Afghans, one German and a Briton - were flown to Kabul from the northern province of Badakhshan, where they were gunned down three days ago at the end of a humanitarian mission. The Taliban claimed responsibility and accused the group of spying and seeking to convert Muslims to Christianity.
Colo. Dentist Among 10 Killed in Afghanistan
6 Americans on Medical Team Slain in Afghanistan
NATO: 3 Service Members Killed in Afghanistan
The Taliban and their allies were responsible for 68 percent of the at least 1,325 civilian deaths recorded by the Afghan Independent Human Rights Commission, the organization said in a report. Twenty-three percent were ascribed to NATO or Afghan government forces.
Responsibility for the remaining 9 percent could not be determined because they occurred in areas that were too dangerous for a thorough investigation, the commission said.
NATO and Afghan government forces have accelerated military operations in the Taliban's southern heartland, a move that brought a sharp increase in allied casualties. Last month a record 66 American troops were killed, compared with 44 in July last year. A record total of 103 international troops, including Americans, died in June, more than triple the figure for the same month in 2009.
The top U.S. and NATO commander, Gen. David Petraeus, has maintained strict curbs on air power and heavy weapons implemented last year by his predecessor, Gen. Stanley McChrystal. Those measures have tamped down the number of civilian deaths but have raised complaints from the ranks that they put soldiers' lives at risk and give an advantage to the Taliban.
Still, a daily drumbeat of violence continues. Three Afghan civilians were killed by insurgent attacks or bombs Saturday, while five NATO service members - three Americans and two Danes - were killed the same day, the military coalition said.
Most of this year's civilian deaths occurred in the Taliban's southern heartland with bombs the biggest single killer, the commission said.
Insurgent bombs were responsible for 425 civilian deaths, with more than 200 of them in June and July. Fighting in Afghanistan traditionally increases during summer months.
Another 122 people were killed in suicide attacks and 197 either directly assassinated or caught in the crossfire of assassination attempts, according to the report.
In the first seven months of 2009, 1,252 civilians were killed - 67 percent of them by insurgents and 23 percent by government-allied forces, the group said.
The U.N. is expected to release its own figures on civilian casualties for the first six months of the year in coming days. In all of 2009, at least 2,412 Afghan civilians were killed in fighting, according to the U.N. That was up 14 percent from 2008.
The bodies of the assassinated medical team, which included three women, were returned to Kabul aboard helicopters of the Afghan counternarcotics agency. The families of the six Americans were formally notified of their deaths after U.S. officials confirmed their identities, said Caitlin Hayden, a spokeswoman for the embassy.
Names of most of the foreigners have not been released by officials.
Officials have said the victims included team leader Tom Little, an optometrist from Delmar, New York, who had lived in Afghanistan for about 30 years, and Dr. Karen Woo, who gave up a job in a private clinic in London to do humanitarian work in Afghanistan.
The team was attacked while returning to Kabul after a two-week mission in the remote Parun valley of Nuristan province about 160 miles (260 kilometers) north of Kabul. The bullet-riddled bodies were found Friday near three four-wheeled drive vehicles in a wooded area just off the main road through a narrow valley in the Kuran Wa Munjan district of Badakhshan.
The gunmen spared an Afghan driver who told police he recited verses from the Islamic holy book the Quran as he begged for his life.
The driver was being questioned by police in Kabul on Sunday, officials said.
"Right now he is with police. As he is the key witness in the investigation, his explanation and information are very important," said Zemeri Bashary, a spokesman for the Interior Ministry. Bashary said they would not be able to say whether the driver was a suspect until the investigation had gotten further.
The U.S. ambassador to Afghanistan decried the killings.
"The Taliban has called this group of medical aid workers spies and proselytizers. They were no such thing. These were selfless volunteers who devoted themselves to providing free and much-needed health care to Afghans in the most remote and difficult parts of your country," Karl Eikenberry said in a statement.
Eikenberry said it was not clear if the Taliban were behind the killings.
"We do not know whether they are responsible or simply taking credit for the cowardly and despicable acts of others," he said.
In northern Kunduz province, meanwhile, gunmen attacked the home of a local police commander, killing the commander, a bodyguard and five other people who were guests at his house, according to provincial government chief Abdul Rahman Aqtash.
In the west, a suicide car bomber killed two police officers Sunday outside Herat city when he struck their vehicle on the road, according to Raouf Ahmadi, a police spokesman. And in southern Kandahar province, another police officer died when a minibus carrying officers back from training hit a bomb, provincial spokesman Zalmai Ayubi said.