Civilian casualties were reported in an airstrike by U.S.-led coalition warplane in retaliation to Taliban militant attack in western Afghanistan Wednesday.
This is the second consecutive day of civilian deaths in coalition force airstrikes in Afghanistan.
Dozens of civilians were killed and many more wounded in air strikes by American warplanes in the southern Afghan province of Kandahar Tuesday.
While the provincial council chief of Badghis province said around 30 civilians were killed in Wednesday's air raid, the American military did not confirm the death toll.
It said in a statement Thursday that the incident is being investigated.
"If we find that innocent people were killed in this incident, we apologize and express our sincere condolences to the families and the people of Afghanistan," said Colonel Greg Julian, a U.S. spokesman.
The NATO forces obtained the air-strike when they came under attack from a group of Taliban militants in Ghormach district of Badghis province.
Six Taliban militants were also killed in the bombing, according to the provincial police chief. He said only two civilians were killed in the attack.
A separate statement from the U.S. military said two other militants were killed Thursday by coalition forces in the south-eastern province of Khost.