At least three dozen Afghan police officers and civilians have been killed in two airstrikes by NATO-led forces, Afghan officials said Sunday.

A NATO military spokesman in Kabul said the coalition was aware of both incidents and had begun investigations.

The reported deaths — of 14 civilians in southern Helmand province Saturday and 22 police officers plus civilians in northeastern Nurestan province Wednesday — are likely to add to long-running tension between Kabul and its Western allies about civilian casualties caused by NATO forces.

President Hamid Karzai on Saturday called for the end of all unilateral NATO military operations and night raids by U.S. Special Operations troops. In a statement issued Sunday, the president strongly condemned the civilian deaths in Helmand, which he said were caused by U.S. troops.

“American and NATO troops have been repeatedly warned that their willful and inappropriate operations cause daily the killings of innocent and desperate people and that such raids trample underfoot the human and moral values. But it seems that they do not heed,” the statement quoted Karzai as saying.

Afghan officials in Helmand said the 14 dead were five girls, two women and seven boys. They sent to the news media images of several dead children who they said had been killed during Saturday’s bombing by NATO after a skirmish with the Taliban in the province’s Naw Zad district.

In his statement, Karzai termed the deaths of women and children a major mistake and said he had issued his last warning to NATO and U.S. troops.

The air raid Wednesday in Nurestan occurred after militants briefly captured a government building, officials said. There were conflicting accounts about the number of casualties. The province’s police chief, Shams-ur Rahman, said those killed included 70 Taliban fighters, 22 police officers and an unknown number of civilians. The Interior Ministry in Kabul said it was aware of reports of casualties among police and civilians but could not provide details.

Another official in Nurestan said that scores of civilians were killed and that foreign forces prevented provincial authorities from collecting the bodies.

A spokesman for the coalition, Lt. Tyler Balzer, said that teams of Afghan and coalition officials were sent to both sites.

Since the ouster of the Taliban by U.S.-backed Afghan forces in 2001, civilians have borne the brunt of casualties during attacks by insurgents, foreign troops and Afghan forces.

Civilian deaths caused by foreign troops have long been a key source of tension between Karzai and the United States.

Salahuddin is a special correspondent. Staff writer Joshua Partlow contributed to this report.