House Republicans are calling for a special counsel to determine whether Attorney General Eric Holder misled Congress during his testimony to the House Judiciary Committee on Operation Fast and Furious, Fox News has learned.

House Judiciary Committee Chairman Lamar Smith, R-Texas, was sending a letter to President Obama on Tuesday arguing that Holder cannot investigate himself, and requesting the president instruct the Department of Justice to appoint a special counsel.

The question is whether Holder knowingly made false statements of fact under oath during a Judiciary Committee hearing on May 3. At the time, Holder indicated he was not familiar with the Bureau of Alcohol, Tobacco, Firearms and Explosives program known as Fast and Furious until about April 2011.

“I’m not sure of the exact date, but I probably heard about Fast and Furious for the first time over the last few weeks,” Holder testified.

However, newly discovered memos suggest otherwise. For instance, one memo dated July 2010 shows Michael Walther, director of the National Drug Intelligence Center, told Holder that straw buyers in the Fast and Furious operation “are responsible for the purchase of 1,500 firearms that were then supplied to the Mexican drug trafficking cartels.”

Other documents also indicate that Holder began receiving weekly briefings on the program from the National Drug Intelligence Center “beginning, at the latest, on July 5, 2010,” Smith wrote.

“These updates mentioned, not only the name of the operation, but also specific details about guns being trafficked to Mexico,” Smith wrote in the letter to Obama.

“Allegations that senior Justice Department officials may have intentionally misled members of Congress are extremely troubling and must be addressed by an independent and objective special counsel. I urge you to appoint a special counsel who will investigate these allegations as soon as possible,” Smith wrote.

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