Washington (CNN) -- In a demand for fast -- if not furious -- action, Congressional investigators have given the FBI and the Drug Enforcement Administration just one week to produce documents to aid their investigation of a controversial gun-purchasing operation by the Bureau of Alcohol, Tobacco, Firearms and Explosives.
A senior FBI official said the bureau expects to provide answers to all the questions raised by congressional investigators in their July 11 letter to Director Robert Mueller by the July 25 deadline. A DEA official indicated his agency would also respond to a July 15 inquiry from congressional investigators by the imposed July 29 deadline.
Sen. Charles Grassley, R-Iowa, and Rep. Darrell Issa, R-California, sent letters to the agency heads demanding specific information and documents. On Monday, a spokesman for Issa said the DEA was expected to respond by Friday, but there was no response yet from the FBI.
The letters follow a closed July 4 meeting between investigators and embattled ATF Acting Director Ken Melson, who sources said implicated FBI and DEA involvement in the controversial firearms purchasing project. Federal law enforcement officials familiar with the case say Melson is fighting to keep his job, and is unwilling to be a "fall" guy for "Operation Fast and Furious."
"In recent weeks we have learned of the possible involvement of paid FBI informants in Operation Fast and Furious," the letter to FBI Director Robert Mueller said. "Specifically, at least one individual who is allegedly an FBI informant might have been in communication with, and was perhaps even conspiring with at least one suspect whom ATF was monitoring," the letter from Issa and Grassley said.
The ATF program allowed thousands of heavy-duty assault-type weapons to be illegally purchased. Many of the weapons were recovered at crime scenes in Mexico.
The letters call for answers to a series of questions about informants, FBI and DEA officials in Arizona and Texas and the case agent from Tucson in charge of the Brian Terry murder investigation. Border Patrol Agent Terry was killed in Arizona last December. Two weapons that were allowed to "walk" under the Fast and Furious program were found at the crime scene.
The letters also demand e-mails, memoranda, briefing papers and handwritten notes relating to the operation.