At least 3,545 noncombatants died and another 7,457 were injured by fighting last year

* 11,002 civilian deaths and injuries recorded in 2015

* Heavy fighting in Kunduz, attacks in Kabul behind 4 percent rise

* UN urges both sides to limit casualties (Adds comment from Afghan government, Taliban)

By Josh Smith

KABUL, Feb 14 (Reuters) - Civilian casualties of the war in Afghanistan rose to record levels for the seventh year in row in 2015, as violence spread across the country in the wake of the withdrawal of most international troops, the United Nations reported on Sunday.

At least 3,545 non-combatants died and another 7,457 were injured by fighting last year in a 4-percent increase over 2014, the international organization said in its annual report on civilian casualties.

"The harm done to civilians is totally unacceptable," Nicholas Haysom, the head of the U.N. Assistance Mission in Afghanistan, said in a statement.

Fighting between Western-backed government forces and insurgent groups meant more non-combatants are being caught in the crossfire, investigators wrote, pointing to two developments in particular which pushed casualties up.

Heavy fighting in the northern city of Kunduz, which briefly fell to the Taliban in late September, and a wave of suicide bombs which killed and wounded hundreds of people in the capital Kabul last year were the main factors behind the rise, while elsewhere casualties fell.

"In most parts of Afghanistan in 2015, civilian casualties decreased," Danielle Bell, director of the U.N. human rights programme in Afghanistan, told a news conference.

Ground engagements were the leading cause of civilian casualties at 37 percent, followed by roadside bombs at 21 percent and suicide attacks at 17 percent.

Women and children were hard hit, as casualties among women spiked 37 percent while deaths and injuries increased 14 percent among children.

Casualties attributed to pro-government forces jumped 28 percent compared to 2014 to account for 17 percent of the total.

A 9-percent rise in civilian casualties caused by international forces was attributed largely to a U.S. air strike in October on a Doctors Without Borders hospital that killed 42 staff, patients, family members and injured another 43.

Overall 103 civilians were killed and 67 wounded by foreign forces last year, the report found.

A statement from President Ashraf Ghani accused the Taliban of violating international law. It said Afghan security forces underwent regular training to ensure the protection of civilians and were liable to investigation if any breaches occurred.

As in past years, insurgent groups like the Taliban were blamed for most civilian deaths and injuries, at 62 percent. Investigators accused insurgents of using tactics that "deliberately or indiscriminately" caused harm to civilians.

The Taliban rejected the report, describing it as "propaganda compiled at the behest of occupying forces" and said the government in Kabul and its U.S. ally were the major causes of deaths and injuries.

UN officials said that pledges from both sides to limit casualties had not been backed up.

"The report references commitments made by all parties to the conflict to protect civilians, however, the figures documented in 2015 reflect a disconnect between commitments made and the harsh reality on the ground," Bell said.

She said the expectation of continued fighting in the coming months showed the need for both sides to take immediate steps to prevent harm to civilians.

Since the United Nations began recording civilian casualties in Afghanistan in 2009, it has documented nearly 59,000 deaths and injuries. (Additional reporting by James Mackenzie; Editing by Michael Perry and Ros Russell)

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