Three U.S. soldiers were wounded in an explosion in southern Afghanistan on Monday, the military said, in the latest sign of rising violence in the run-up to October's presidential election. Also on Monday, a police chief in the southern city of Kandahar city narrowly escaped a bomb blast officials blamed on followers of the Taliban regime bent on disrupting the poll. The American soldiers and their translator were wounded 55 km (34 miles) east of Qalat, capital of Zabul province, the U.S. military said in a statement. They were conducting operations when the incident occurred, it said, adding that all were evacuated to neighboring Kandahar province's airfield for treatment. It did not give more details. On Friday, one U.S. soldier was wounded by a remote-controlled bomb as a military convoy passed a parked car containing explosives on the road between the U.S. airfield and Kandahar city. Scores of U.S.-led troops have been killed and wounded in action in Afghanistan since late 2001, after the Taliban regime was overthrown for harboring al Qaeda chief Osama bin Laden. There are around 20,000 soldiers led by the U.S. military in Afghanistan hunting al Qaeda and Taliban guerrillas and helping to improve security ahead of a presidential election in October and a parliamentary poll in April. **PHOTO CAPTION*** More vigilantes may be operating in Afghanistan similar to three US citizens facing trial for setting up a private prison in Kabul, including Jonathan Idema (C), a US military spokesman said. (AFP)