The heated Congressional investigation into the botched Bureau of Alcohol, Tobacco, Firearms and Explosives program Operation Fast and Furious reached a whole new level on Friday.

New emails obtained by the Los Angeles Times appear to show senior Obama administration and White House officials were briefed on the gun-walking operation. The three White House officials implicated by the LA Times’ reporting are Kevin M. O’Reilly, the director of North American Affairs for the White House national security staff; Dan Restrepo, the president’s senior Latin American advisor; and Greg Gatjanis, a White House national security official.

The emails were sent between July 2010 and February 2011, before the scandalous ATF program was exposed, according the LA Times.

The LA Times says a senior administration official denies that the emails which lead Fast and Furious ATF agent William Newell sent to O’Reilly — who later briefed Restrepo and Gatjanis –included details on “investigative tactics” used in the program. By “investigative tactics,” the White House means how ATF agents facilitated the sale of firearms to drug cartels via “straw purchasers,” or people who could legally buy guns in the U.S. but did so with the intention of selling them to individuals who would traffic them to Mexico.

Those emails apparently show Newell and O’Reilly discussing how the program was affecting Mexico.

Another explosive new detail that emerged on Thursday was a set of documents showing senior officials in Phoenix attempting to cover up a connection between Fast and Furious weapons and U.S. Border Patrol agent Brian Terry’s death.

In a letter sent to Ann Scheel, the new acting U.S. Attorney for Arizona, House Oversight committee chairman Rep. Darrell Issa and Sen. Chuck Grassley wrote that high-ranking Phoenix officials tried to “prevent the connection [between Terry’s death and Fast and Furious weapons] from being disclosed.”

Internal emails also show that recently resigned Arizona U.S. Attorney Dennis Burke and his deputy Emory Hurley made the decision because “this way we do not divulge our current case (Fast and Furious) or the Border Patrol shooting case.”

UPDATE 3:04 p.m.:

Though the White House has claimed these newly discovered emails didn’t contain any details on the “investigative tactics” officials used in Operation Fast and Furious, one comment has surfaced suggesting otherwise. Politico reports that, in an August 18, 2010, email to O’Reilly, Newell described the details of what was going on.

“I appreciate and respect the struggles the [U.S. Attorney’s Office] has to go through with juries in this State to convince them of the illegality of this. We routinely have ‘straw’ purchasers tell us that ‘yeah, I knew what I was doing was wrong but the money was good and who cares — the guns are going to Mexico right?’” Politico reports Newell wrote to O’Reilly last year.

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