Taliban militants attacked a police checkpoint in southern Afghanistan and killed 16 officers, the Interior Ministry said Monday. Five Afghan soldiers were killed in attacks elsewhere. Spain's King Juan Carlos, meanwhile, made an unannounced visit Monday to Spanish troops based in western Afghanistan, the royal palace said. The policemen were manning a checkpoint in the Maywand district of Kandahar province on Saturday when a large group of militants attacked them, said Zemerai Bashary, the Interior Ministry spokesman. "We still have not found the bodies, but police in Kandahar have launched a search operation," Bashary said.