At least 40 Afghan civilians have been killed and 28 more injured as an airstrike of the US-led Coalition forces hit a wedding gathering in southern Afghanistan's Kandahar province, officials and local villagers said Wednesday.

The US-led troops called in gunship helicopters Monday afternoon to retaliate on militants who earlier that day attacked them at Wech Baghtu village in Shah Wali Kot district of Kandahar. However, the air bombing hit a wedding party being held near the hilly area where the Taliban insurgents' firing came from, according to locals.

Condemning the incident, Afghan President Hamid Karzai was saddened by "the killing of 40 civilians and injuring of 28 others in a Coalition air strike," a statement from his office said. "President Karzai has stressed repeatedly in the past that civilian casualties should be avoided but the Coalition forces usually carry out bombing without planning."

Haji Roozi Khan, owner of the house where the wedding ceremony was held, earlier told Xinhua that at least 37 civilians including10 women, 23 children were killed and 35 others including the bride wounded in the bombing and firing of Coalition forces which lasted from 2 p.m. Monday until late that night.

A Xinhua reporter at the scene Wednesday afternoon saw many locals there were still searching the debris for their relatives' dead bodies. Locals said the casualties' figure was expected to rise.