A U.S. law enforcement operation intended to crack down on major weapons traffickers on the Southwest border spiraled out of control as federal agents were told by superiors to "stand down" and ignore weapons bought in Arizona headed for Mexico, a House panel heard Wednesday. Three federal firearms investigators told the House Oversight and Government Reform committee that they wanted to "intervene and interdict" loads of guns, but were repeatedly ordered to step aside. "Allowing loads of weapons that we knew to be destined for criminals -- this was the plan," John Dodson, a Bureau of Alcohol, Tobacco, Firearms and...