KANDAHAR, Afghanistan - A suicide bomber targeted a U.S.-led coalition convoy in eastern Afghanistan on Monday, while Afghan security forces clashed with the Taliban militants in the south, leaving nine militants dead, officials said Monday.

The blast in Khost province killed the bomber, said Gen. Mohammad Ayub, the provincial police chief. There were no immediate reports of casualties among the U.S. forces.

A spokesman for the U.S.-led coalition said they were aware of a car bomb explosion in the east but did not have further details on the incident.

In the south, Afghan police and army soldiers battled militants Sunday in Kandahar province's Shohrawak district, said provincial police chief Sayed Agha Saqib.

The joint Afghan forces thwarted a planned militant ambush at the district chief's compound, and the ensuing clash left nine militants dead, Saqib said. Authorities recovered the militants' bodies and weapons, he said.

During a cleanup operation after the battle, a roadside bomb hit a police vehicle in the same district, killing five officers and wounding two others, Saqib said.

Violence in Afghanistan has risen sharply during the last two months. More than 3,700 people, mostly militants, have been killed in insurgency-related violence this year, according to an Associated Press tally of casualty figures provided by Western and Afghan officials.

In the northeastern province of Badakhshan, police arrested a man with a suicide vest on Monday who said he was from Kazakhstan, said Shamsul Rahman, the deputy governor. The man said other suicide bombers were in Badakhshan, Rahman said, prompting police to launch a search operation.