Attorney General Eric Holder testified before Congress today in what was the most confrontational hearing over the botched "gunwalking" scheme, a.k.a. Operation Fast and Furious, to date. The investigation has been going on for a year at this point and, as Wired.com's Danger Room reporter Robert Beckhusen writes, it's reached a kind of stalemate, in which the GOP demands documents to prove whether Holder knew about the operation before it became public while Holder insists the Justice Department has already provided "virtually unprecedented access" to Congress. So what's left to do with practically no agreement between the two sides? Exchange a whole lot of fiery, combative statements. Here were the flash points:

Issa and Holder fire off opening remarks Marking the one-year anniversary of the investigation, Congressman Darrell Issa promises he won't let another Groundhog's Day go by without bringing justice to Brian Terry, the border patrol agent shot and killed by a gun sold in the Fast and Furious operation. Holder says he took action as soon as he learned of the mission. 

Congresswoman Ann Marie Buerkle plays the death card After calling for Holder's resignation, Rep. Buerkle poses a loaded question. "Let me ask it this way: How many more Border Patrol agents really have to die as part of Operation Fast and Furious for you to take responsibility?” Holder replies that the question is "beneath a member of Congress":

Who told you about Fast and Furious?! Issa probes Holder on which DOJ staffer first told him of the scandal. Holder dances around the question and suggests he may have first found out through the media:

Congressman Raul Labrador calls for Holder's resignation. This time, Holder doesn't mince his words after the Idaho congressman asks him to step down. "That was among the worst things I think I've ever seen in Congress," Holder said. "Maybe this is the way you do things from Idaho or wherever you're from [but] what you have just done just done is, if nothing else, disrespectful:

Holder's full response is here