Last year was the deadliest on record for civilians in the Afghan war, with 3,021 killed as insurgents ratcheted up violence with suicide attacks and roadside bombs, the United Nations said on Saturday.
Taliban-affiliated militants were responsible for more than three-quarters of the civilian deaths in 2011, the fifth year in a row in which the death toll went up, the UN said.
The figures were a grim testament to the violence the Taliban and allied Islamist militants can still unleash in Afghanistan, even as Nato begins to map out plans for international troops to draw down and give Afghan security forces the main responsibility for fighting insurgents by the end of 2014.
"A decade after the war began, the human cost of it is still rising," said Georgette Gagnon, director for human rights for the UN mission in Afghanistan.
The number of civilian deaths was up 8% over 2011.
Deaths in suicide bombings jumped dramatically to 450, an 80% increase over the previous year.
While the number of suicide attacks remained about the same, they killed more civilians. On December 6, a bomber detonated his explosives-filled vest at the entrance of a mosque in Kabul, the capital, killing 56 worshippers during the Shiite Muslim rituals of Ashoura.
It was the single deadliest suicide attack since 2008.
The single biggest killer of civilians remained the ever-more-powerful roadside bombs planted by insurgents.
The homemade explosives, which can be triggered by a footstep or a vehicle and are often rigged with enough explosives to destroy a tank, killed 967 people - nearly a third of the total.
The 130,000-strong coalition force led by the US says it has been hitting the Taliban hard, seizing their one-time strongholds while expanding and training the Afghan army and police to take over primary responsibility for waging the decade-old war.
Still, insurgent attacks are killing more and more civilians, according to a detailed annual UN report.
The increased presence of security forces managed to reduce civilian casualties in the troubled southern provinces of Helmand and Kandahar, but the UN said insurgents simply pulled back and focused instead on areas along the country's border with Pakistan, relying more on roadside bombs and suicide attacks in places like bazaars, schoolyards, footpaths, and bus stations.
"The tactics have changed," said Jan Kubis, the UN secretary general's special representative to Afghanistan.
"The anti-government forces being squeezed in certain areas ... move to some other areas and again use these inhuman, undiscriminating weapons like human-activated explosive devices and suicide attacks."