 The Justice Department confirmed that the .50-caliber rifle was bought in July 2010 in a straw purchase by someone not known to the ATF at the time, and stated the weapon was not associated with any other crime.In a letter to Congressional leaders, Assistant Attorney General Peter Kadzik, head of the Justice Department's legislative affairs office, wrote, "ATF and the department deeply regret that firearms associated with Operation Fast and Furious have been used by criminals in the commission of violent crimes, particularly crimes resulting in the deaths of civilians and law enforcement officials.