A U.S. Justice Department investigation released Wednesday said that Attorney General Eric Holder did not know about Operation Fast and Furious, a federal undercover sting that allegedly allowed some 2,000 weapons to be smuggled into Mexico.

The much-awaited report documented mistakes by several officials, but found "no evidence that Attorney General Eric Holder knew of the botched effort to trace the flow of guns to Mexico's drug cartels prior to its unraveling in January 2011."

Holder said the report confirms what he and other officials in his agency had been saying for many months: that top Justice Department officials were not aware of and did not authorize the strategy behind Fast and Furious.

A U.S. congressional committee filed a civil suit last month against Holder demanding that he hand over additional documents concerning Fast and Furious.

The chairman of the House Oversight Committee, Rep. Darrell Issa (R-Calif.), filed the suit asking the U.S. District Court for the District of Columbia to require Holder to turn over the documents subpoenaed by the congressional panel in October 2011.

The committee earlier voted to hold Holder in contempt for his refusal to deliver the documents.

Fast and Furious was launched in 2009 by the Bureau of Alcohol, Tobacco, Firearms and Explosives' Phoenix office and shut down in late 2010 after guns traced to the program were linked to the killing in Arizona of U.S. Border Patrol agent Brian Terry.

"Our review of Operation Fast and Furious and related matters revealed a series of misguided strategies, tactics, errors in judgment, and management failures that permeated ATF Headquarters and the Phoenix Field Division, as well as the U.S. Attorney's Office for the District of Arizona," the inspector general's office said. EFE