Foreign and Afghan forces accidentally killed five children in two separate operations Monday, further undermining President Hamid Karzai after he demanded a halt to attacks in civilian areas.

Afghan officials have accused forces from the U.S. and other countries of killing dozens of civilians in recent weeks. The deaths have inflamed tensions across the country and weakened public support for both Karzai's government and a continued foreign troop presence in Afghanistan.

NATO said it accidentally killed three children in an artillery strike in the east on Monday after insurgents attacked its troops in the area. One artillery round slammed into a house in Gayan district of the eastern Paktika province, killing the children.

A NATO statement said it "deeply regrets this accident, and an investigation as to the exact circumstances of this tragic event is now under way."

Afghan government officials were not immediately available for comment on Monday, which was a national holiday.

In a separate incident, U.S. troops backed by Afghan intelligence agents killed a man and his two children during a raid near the capital Kabul, said police officer Qubaidullah, who like many Afghans goes by one name.

However, 1st Lt. Nathan Perry, a U.S. coalition spokesman, said no American troops took part in the operation. NATO said it could not confirm its troops had participated.

Angry men gathered at the victims' house in the Utkheil area east of Kabul where the three bodies were displayed inside a mud-walled compound, said relative Yahya Khan.

The latest deaths are sure to deepen tensions between the Afghan government — under pressure from an increasingly irate public — and foreign forces in the country.

Karzai has castigated Western military commanders over civilian deaths resulting from their raids in Afghan villages, and urged them to take their fight into Pakistan's tribal areas, where Taliban and other militants appear to be operating freely. The Taliban and other insurgents use the deaths as leverage to turn Afghans away from the government, he says.

Last month, Karzai called on American and NATO commanders to stop their airstrikes in civilian areas of Afghanistan, and instead go after terror centers in neighboring Pakistan.

But American and NATO officials say they do all they can to minimize civilian deaths and accuse militants of hiding and firing at them from civilian homes.

Afghan officials accuse foreign forces of killing up to 90 civilians during an Aug. 22 operation in the country's west. The U.S. denies the accusation, saying its troops and Afghan commandos killed 25 militants and five civilians in the operation.

In another sign that the civilian deaths are undermining NATO's mission, the alliance issued an unusual statement Sunday warning that the Taliban planned to make a false claim about the killings of civilians in the southern Helmand province, where military operations have been ongoing.

NATO said it was anticipating a militant claim that up to 70 civilian were killed by the international troops in the south based on information from "a reliable source."

Separately, the military alliance also said its forces had helped more than 20 wounded civilians who approached two of its bases in Helmand province.

NATO said the civilians were wounded in two separate incidents involving insurgents.

"Insurgents ransacked three compounds and killed three women and an unspecified number of children," in Helmand's Sarevan Qaleh village, NATO said in a statement, quoting one of those wounded. "He then reported that the insurgents had shot him in both kneecaps before fleeing," it said.

The claims could not be independently verified and have not been reported by Afghan authorities.

NATO said it condemns the "use of the plight of innocent civilians for propaganda gain by insurgents."

Claims of civilians deaths can be tricky because independent observers are routinely unable to reach the areas of the conflict.

The issue is a particularly sensitive topic in Afghanistan following the Aug. 22 bombing of the village of Azizabad in Herat province by the U.S.-led coalition. A preliminary U.N. report has backed the findings of an Afghan government commission that said up to 90 civilians were killed, despite U.S. denials.

The U.S. has long said insurgents use false civilian death claims as a propaganda tool to undermine support for international forces and the government of Afghan President Hamid Karzai.

The top NATO spokesman in Afghanistan, Brig. Gen. Richard Blanchette, said Saturday that the U.S.-led coalition, Afghan government and United Nations would jointly investigate the Aug. 22 raid, but the Afghan government has still not confirmed it will take part.