By Matt Robinson
KABUL (Reuters) - Targeted killings of civilians in Afghanistan doubled last year, the United Nations said on Wednesday, as an expanding insurgency strikes at Western efforts to build up the Afghan government and security forces.
In an annual report, the United Nations said 2010 marked the most lethal year for noncombatants in the nearly decade-old war, with a 15 percent increase in the number of civilians killed to 2,777 -- continuing a steady rise over the past four years.
Insurgents were responsible for 75 percent of those deaths.
U.N. Assistant Secretary General for Human Rights, Ivan Simonovic, said the U.N. rights officials had been "in communication with the Taliban," offering guidance to reduce civilian casualties.
U.N. officials declined to elaborate on the contacts.
Abductions rose 83 percent, and violence continued to spread from the south to the north, east and west, the report said. Civilian deaths in the north, in particular, rose 76 percent.
But the most "alarming" trend, it said, was a 105 percent increase in the targeted killing of government officials, aid workers and civilians perceived to be supportive of the Afghan government or NATO-led foreign forces.
The tactic threatens to undermine further the handover of responsibility for security to the Afghan government, police and army starting this year, as Washington and its NATO allies seek to draw down their combined 150,000-strong force.
Of 462 assassinations in 2010, half occurred in Taliban strongholds in the south, where the United States says it has made most gains from a 30,000-strong troop surge aimed at turning the tide of the war.
In many parts of Afghanistan, local governors live behind sandbags on U.S. military outposts and government officials rarely travel to the areas they are supposed to run.
"People are afraid to go and vote, people are afraid of being elected, people are afraid of actually participating in civilian society," U.N. envoy to Afghanistan Staffan de Mistura told a news conference.
The report, issued jointly with the Afghanistan Independent Human Rights Commission, said the social and psychological impact of assassinations were "more devastating than a body count would suggest."
Civilian assassinations were up 588 percent and 248 percent in Helmand and Kandahar provinces respectively, the main strongholds of the Taliban and the focus of a U.S. troop surge.
The report noted a 26 percent decline in the number of civilian deaths caused by coalition and Afghan forces.
Yet the killing of civilians in NATO operations has re-emerged as a major source of friction between Kabul and its Western backers.
Last week, NATO helicopters gunned down nine Afghan boys collecting firewood, drawing condemnation from Afghan President Hamid Karzai and apologies from President Barack Obama and his top commander in Afghanistan, General David Petraeus.
U.S. Defense Secretary Robert Gates repeated the apology on Monday during a visit to assess security progress before Washington starts gradually withdrawing troops in July.
Casualties among women rose 6 percent in 2010, and among children by 21 percent, while "the spread and intensity of the conflict meant that more women and children had even less access to essential services such as healthcare and education."
Suicide attacks and homemade bombs claimed most lives.
Of the 440 deaths attributed to NATO and Afghan forces, 171 were caused by aerial attacks, sharply down on 2009 as a result of tightened rules of engagement.
The report noted a decline in civilian casualties in "night raids" by foreign forces, a tactic ramped up under Petraeus to the anger of Afghans and Karzai's government.
It attributed the drop to stricter regulations, but expressed concern about "consistent implementation" and a "persistent lack of transparency on investigations and accountability."
(Editing by Miral Fahmy)