Less than one week after the House voted to hold Attorney General Eric Holder in contempt, Sen. Charles Grassley (R-Iowa) is demanding additional information from the Justice Department regarding the botched “Fast and Furious” gun-tracking operation.

On Tuesday, Grassley, ranking member of the Senate Judiciary committee, sent a letter to Holder questioning who within the Justice Department knew of a Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) memorandum reportedly circulated one day prior to the DOJ denying allegations of sanctioned “gunwalking” to lawmakers.

“I believe the Department should have been abundantly aware of allegations of gunwalking as there was more than one ATF agent providing information to Department components before the February 4, 2011, letter was sent to Congress,” he wrote.