Afghan officials say a suicide bomber has killed three people in the capital of Kabul, while fighting intensified with Taliban militants in the southwestern part of the country. Police in Kabul say the bomber exploded his car near a coalition military convoy as it traveled down a busy street. The blast killed three bystanders, including a child. A coalition spokesman, U.S. Lieutenant Colonel Dave Johnson, says none of the soldiers were hurt.In southwestern Farah province, police officials say Afghan and NATO forces inflicted heavy casualties in clashes with Taliban militants. They say Afghan troops surrounded the Taliban as they gathered in the Bala Buluk district. NATO forces then called in an airstrike. Afghan officials say 30 Taliban militants were killed. Two Afghan soldiers and a policeman also died in the clash.