Q+A-Civilian casualties in Afghanistan

A U.S Marine searches an Afghan man for weapons in the Golestan district of Farah province May 8, 2009.

KABUL (Reuters) - President Hamid Karzai is "very serious" about a demand for foreign forces in Afghanistan to halt air raids to avoid civilian deaths, even though it was rebuffed by a top U.S. security official, his spokesman said on Monday.

Afghans are furious about the bombing of two villages in Western Farah province during a drawn-out battle last week, when homes full of civilians were hit. Karzai put the death toll at up to 130 people.

Here are a few facts about civilian deaths in Afghanistan.

HOW BAD IS THE PROBLEM?

The growing strength of the insurgency across much of Afghanistan has led to fiercer fighting and a fast-rising civilian death toll from operations by foreign troops.

Civilian deaths caused by pro-government forces, including U.S., NATO and Afghan security forces, rose nearly a third in 2008 from a year earlier to 828, the United Nations said.

Airstrikes accounted for 552, or well over half, the total.

The deaths of ordinary Afghans are undermining support for the U.S. and NATO-led mission which was originally welcomed in parts of the country for toppling the Taliban in 2001.

HOW HAS IT AFFECTED U.S. RELATIONS WITH KABUL?

Civilian casualties have become a deep source of friction between Karzai and his U.S. backers, especially since an incident last August in which Afghan and U.N. investigators say U.S. strikes killed 90 civilians.

Washington initially denied killing large numbers of civilians in that incident, only to acknowledge three months later it had killed at least 33.

The Farah strikes have sparked a new crisis, with apparent disagreement between the Afghan government and U.S. military over the death toll and the possible role of the Taliban.

WHAT HAS THE U.S. TRIED TO DO ABOUT IT?

Since last year, U.S. and NATO forces have established new drills intended to reduce the number of civilian casualties.

They also say they now launch immediate investigations alongside Afghan authorities into all reports of civilian deaths and apologise more quickly than before. But civilians are killed still.

WHY IS IT SO DIFFICULT TO AVOID?

U.S. commanders acknowledge that part of the problem has been a shortage of troops on the ground and large, diverse terrain, which makes forces reliant on air strikes to a greater degree than, for example, in Iraq. They blame insurgents for launching attacks from civilian areas and using civilians as human shields.