Insurgent attacks on Afghan government employees soared by 700 percent last year even as the overall 2012 civilian death toll from the war fell for the first time in six years, the UN said Tuesday.
Targeted killings of women in government service by Taliban-led insurgents were "particularly disturbing", the UN mission in Afghanistan said in its annual report on civilian casualties.
A total of 2,754 civilians died in the conflict last year, a 12 percent drop from 2011, taking the toll over the past six years to 14,728, the report said.
"While the overall incidence of civilian casualties decreased in 2012, anti-government elements increasingly targeted civilians throughout the country and carried out attacks without regard for human life," it said.
Civilian casualties among perceived government supporters, including government employees, religious leaders, tribal elders and people involved in peace efforts rose 108 percent to 1,077.
"Of these, killings and injuries to civilian government employees increased by a staggering 700 percent," the report said.
"Particularly disturbing were targeted killings of women by anti-government elements demonstrated by the killings of the head and deputy head of the Laghman Department of Women's Affairs in July and December 2012."
Overall, insurgents were responsible for 81 percent of civilian casualties, while eight percent were caused by Afghan and NATO forces, the report said. The other 11 percent could not be attributed to either party.
Civilian casualties caused by pro-government forces, including NATO air strikes, dropped more than 40 percent over the previous year, the report said.
The statistics will be welcomed by the NATO military leadership in Afghanistan, which is regularly under fire from President Hamid Karzai over civilians killed by air strikes.
Karzai ordered an end to Afghan security forces calling in NATO air strikes after the reported deaths of 10 civilians in an attack last week.
Civilian casualty figures for the first half of 2012, published by the United Nations in August, showed a 15 percent fall on the same period in 2011.
"The decrease in civilian casualties UNAMA documented in 2012 is very much welcome," said Jan Kubis, UN special representative in Afghanistan.
"Yet, the human cost of the conflict remains unacceptable," he said, pointing to the indiscriminate use of roadside bombs by insurgents as the single biggest killer of civilians.
The steep increase in the targeting of civilians perceived to be supporting the government was "another grave violation of international humanitarian law", he said.
"Particularly appalling is the use of suicide attacks including those carried out by brainwashed children to murder civilians which is also a clear breach of the norms of Islam."
Kubis welcomed statements from the Taliban leadership urging its fighters to protect civilians, but added that without enforcing these directives "all that remains are only words".
The Islamist militants have waged an 11-year insurgency against the Western-backed government in Kabul since being ousted from power in a US-led invasion in 2001.
The US and NATO have around 100,000 troops in Afghanistan, but the vast majority of them will leave next year, with Afghan forces progressively taking over.