US commander apologises over Afghan civilian deaths

Petraeus's personal apology came hours after President Hamid Karzai issued an angry statement saying nine young children died in Tuesday's strike as they collected firewood in Darah-Ye Pech district of northeastern Kunar province.

Civilian casualties in foreign military operations against the Taliban have been high on Afghanistan's political agenda recently, highlighting tensions between Karzai and the West before a planned limited withdrawal of foreign troops from July.

The Afghan army and police are due to take control of security in their own country from 2014.

A NATO International Security Assistance Force (ISAF) statement made no reference to the age of those who died in the attack.

The incident happened after an insurgent rocket attack on a military base prompted coalition forces to return fire, including with air power, it said.

Petraeus has now ordered all helicopter crews to be re-briefed on the need to keep civilian casualties "to the absolute minimum" and troops could face disciplinary action over the strike, the ISAF statement added.

Karzai had earlier criticised foreign forces on civilian deaths, saying they would face "huge problems" if the "daily killing of innocent civilians" did not stop.

About 150 people demonstrated in the town of Asadabad, the capital of Kunar, over the deaths, shouting anti-American slogans, witnesses said.

Civilian casualties during international military operations against insurgents are a source of friction between the Kabul government and its Western backers.

Karzai argues that such incidents risk draining support away from his administration and towards the Taliban.

The Afghan president has long insisted that international forces deployed to the country should focus their efforts on militant hideouts across the border in neighbouring Pakistan.

Earlier this week, an official delegation appointed by Karzai accused international forces of killing 65 civilians in recent, separate operations elsewhere in Kunar.

In that case, though, ISAF said there were only a handful of civilian injuries.

Human rights watchdog the Afghanistan Rights Monitor said last month that 2010 was the deadliest year for Afghan civilians since the US-led invasion in 2001 ousted the Taliban.

At least 2,421 civilians were killed last year, it said, blaming the Taliban and other insurgents for more than 60 percent of the dead. At least 217 died in air strikes by international forces, it added.

ISAF spokesman Brigadier-General Josef Blotz told reporters following Petraeus's apology that progress had been made in limiting casualties of civilians.

Karzai is currently in London, where he was due to visit injured British soldiers who served in Afghanistan.