KABUL -- Afghan officials said yesterday a NATO airstrike inadvertently killed several Afghan soldiers and policemen a day earlier in northwestern Afghanistan.

The airstrike took place amid fighting in Badghis province as Afghan and U.S. troops were looking for two American paratroopers who disappeared in the area Wednesday.

The U.S. military said the soldiers on the search operation came under an attack that killed four Afghan soldiers and two policemen, and wounded five American soldiers and 17 Afghan security forces.

Afghan officials said the troops were killed in a NATO airstrike that hit a coalition base in the area or hit near it. The district's mayor, Abdul Shukor, put the death toll at 20 -- 6 Afghan soldiers, 2 policemen and 12 civilians. Mr. Shukor described the area of the bombing as a military checkpoint near a warehouse.

A NATO statement said authorities were investigating whether "close air support" caused some of the casualties. A U.S. military spokesman, Lt. Col. Todd Vician, said earlier yesterday that the casualties resulted from a "hostile engagement, not an accident." He said he had no reports of civilian casualties in the area.

The Taliban said earlier that the two soldiers had drowned and that it had found the bodies. A parliament member from Badghis, Amir Tawakal, said the soldiers drowned while fishing. U.S. officials did not confirm that the soldiers had died.

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