Several hundred villagers protested Wednesday against coalition strikes that they claim killed scores of civilians, including nine boys, in a hotbed of the insurgency in the northeast. NATO has contested the claims saying armed insurgents, not civilians, were killed.

Civilian casualties have long been a source of friction between Afghan President Hamid Karzai and the US-led international force fighting in Afghanistan. Karzai's office issued a statement condemning the NATO strike.

"Innocent children who were collecting fire wood for their families during this cold winter were killed. Is this the way to fight terrorism and maintain stability in Afghanistan?" Karzai asked in the statement. He said NATO should focus more on "terrorist sanctuaries" a phrase he typically uses when referring to Taliban refuges in neighbouring Pakistan.

Noorullah Noori, a member of the local development council in Manogai district, said that four of the nine boys killed were age 7, three were age 8, one was nine years old and one was 12. Another child was wounded, he added.

He said the children were gathering wood under a tree in the mountains on Tuesday about a half kilometre from a village in Manogai district.

"I myself was involved in the burial...yesterday we buried them at 5pm"  said Noori.

He said that during the four-hour demonstration, protesters chanted "Death to America" and "Death to the spies," a reference to what they said was bad intelligence given to helicopter weapons teams.

The coalition said it was investigating the villagers' allegations. NATO said coalition forces returned fire after two rockets were fired at a coalition base, slightly wounding a local contractor.

Late last month, tribal elders in Kunar claimed that NATO forces killed more than 50 civilians in air and ground strikes. The international coalition denied that claim, saying video showed troops targeting and killing dozens of insurgents and a subsequent investigations yielded no evidence that civilians had been killed. An Afghan government investigation has said that 65 civilians were killed.

In Logar province on Tuesday four Afghan soldiers and their interpreter were killed by a roadside bomb, according to Din Mohammad Darwesh, a spokesman for the province. He said Wednesday that the soldiers were on a joint patrol with US forces when their vehicle hit the bomb planted in Charkh district.