KANDAHAR (AFP) - A suicide bomber on a motorbike blew himself up near two police vehicles in a border town in southern Afghanistan Sunday, killing six people and wounding 17, police said. The evening rush hour blast in Spin Boldak, on the border with Pakistan, was the latest in a series of attacks on police there by the extremist Taliban who have been waging an insurgency for nearly seven years. The bomber blew himself up near two police vehicles on patrol, Kandahar province police chief Matiullah Khan Qate told AFP. Three policemen were killed and five wounded, he said. Three civilians were killed and 12 were wounded. The blast occurred in a wide road and caused little damage to surrounding buildings. A Taliban spokesman, Yousuf Ahmadi, confirmed that his militia was involved. Police officers are among the Taliban's main targets in an insurgency sweeping Afghanistan. In other violence, a government official said police had ambushed and killed 17 Taliban insurgents in Helmand province on Saturday. The US-led coalition said meanwhile it killed six militants in eastern Afghanistan the same day. And an Afghan army colonel said 10 Taliban were killed in a battle in the southwestern province of Farah Sunday.