The Bush administration will deploy more than 500 additional Border Patrol agents to Arizona to deter illegal immigrants from crossing the U.S.-Mexico border, officials said Tuesday, even as a self-appointed civilian group was preparing to launch its own patrols. An announcement scheduled for today will bring top Homeland Security officials from Washington to a cavernous hangar at an Air Force base near Tucson, home to the U.S. Customs and Border Protection aircraft that patrol the border. Full Story