KABUL, Afghanistan — A U.N. report issued on Saturday said last year was the deadliest on record for Afghan civilians, with 3,021 killed in the war.
It was an 8 percent increase in civilian deaths from 2010. 2011 was also the fifth year in a row that the civilian toll has became steadily worse.
The report said insurgents killed more than three-quarters of the civilians who died, with a steep rise in people killed in suicide bombings. It said roadside bombs were the single biggest killer of civilians, accounting for nearly one in three deaths.
NATO and Afghan security forces were responsible for 410 civilian deaths — about 14 percent of the total.
The figures were a grim testament to the violence that the Taliban and allied Islamist militants can still unleash in Afghanistan, even as NATO begins to map out its plan for international troops to draw down and give Afghan security forces the main responsibility for fighting insurgents by the end of 2014.
The number of civilians killed in suicide attacks jumped dramatically to 450, an 80 percent increase over the previous year as militants set off increasingly powerful bombs in public places.
Insurgent-planted roadside bombs remained the single biggest killer of civilians last year. The homemade explosives, which can be triggered by a footstep or a vehicle, killed 967 people — nearly a third of the total. The United Nations decried the insurgents for using the indiscriminate weapons.
"For much too long, Afghan civilians have paid the highest price of war," said Jan Kubis, the U.N. secretary-general's special representative to Afghanistan.
Last year was the deadliest year for Afghan civilians recorded by the U.N. since it started keeping a detailed civilian casualties in 2007.
Overall, 3,021 civilians died in violence related to the war. Of those, the UN attributed 77 percent to insurgent attacks and 14 percent to international and Afghan troops. Nine percent of cases were classified as unknown.
The number of deaths caused by insurgents was up 14 percent over 2010, the U.N. said.
"It is extremely worrying to see civilian casualties continuing to rise year after year," said Navi Pillay, the U.N.'s High Commissioner for Human Rights . "Behind these numbers is real suffering and loss for families in Afghanistan."
While the total number of civilian deaths caused by international and Afghan forces backing President Hamid Karzai's government dropped by 4 percent from the previous year, the number of civilians killed by air strikes targeting insurgents rose to 187 last year, accounting for nearly half the deaths attributed to coalition and Afghan troops.
The U.N. also noted a shift in where the violence affecting civilians was centered. In 2010, the most civilian casualties were in the southern Taliban strongholds of Helmand and Kandahar, where an increased number of U.S. troops pushed to take back territory from insurgents.
While those two provinces still had the most deaths in 2011, their numbers dropped, while civilian deaths went sharply up in southeastern provinces including Khost and Paktika, as well as the eastern provinces of Kunar and Nangarhar. All those areas lie along Afghanistan's volatile border with Pakistan, where many of the Taliban's leaders and the al-Qaida-allied Haqqani network are believed to be based.
Most of the fighting has shifted to those areas over the past year.