'Civilians die' in Afghan clash

At least three civilians travelling by bus have been killed after militants attacked foreign forces in the Afghan province of Wardak, officials say.

Provincial Governor Haleem Fidai said the civilians were caught in an exchange of fire between the militants and foreign troops.

He said several passengers were also injured in the incident.

President Hamid Karzai has repeatedly called on foreign forces to do more to avoid civilian casualties.

The governor said the militants were using the civilians as cover and that local people had told them not to carry out any attacks in the area as a wedding was taking place there.

The foot patrol opened fire on a car and minibus when they failed to stop after soldiers fired warning shots on the highway between Kabul and the southern province of Kandahar, a spokesman for Nato in Kabul told the Reuters news agency.

He said that the foot patrol was ambushed immediately after the incident while troops were treating the casualties.

Afghanistan has suffered its worst violence in 2008 since US-led and Afghan forces overthrew the Taleban seven years ago.

It is estimated that at least 4,000 people have been killed this year and around a third of the total are civilians.