Afghan police clashed with suspected Taliban militants in southern Afghanistan Wednesday, killing three fighters and detaining four, The Associated Press quoted a police official as saying. The militants were killed and captured between the provinces of Kandahar and Uruzgan, where nine border policemen were killed in a militant ambush on Tuesday, said Matiullah Khan, an officer with border police. Afghan and NATO-led forces also battled suspected militants for nearly five hours in Uruzgan province on Tuesday, leaving 12 Taliban and nine policemen dead, Uruzgan's police chief, Gen. Mohammad Qasem, said. Four militants and 10 Afghan troops also were wounded, he said. The southern clashes came after a suicide bomber blew himself up in a crowd of laborers outside a U.S. military base in eastern Afghanistan on Tuesday, killing as many as 10 people in the deadliest suicide attack in four months.