Congress investigators have given the FBI and DEA until July 25 to produce documents relating to a much-criticized anti-arms trafficking scheme, known as “Operation Fast and Furious.”

Under the Bureau of Alcohol, Tobacco, Firearms and Explosives’ (ATF) Operation Fast and Furious, U.S. officials allowed the sale of thousands of firearms to illegal purchasers in an attempt to trace gun-smuggling routes by Mexican gangs. However, around 1,700 weapons have allegedly gone missing.

Investigators set the deadline following a meeting with ATF Acting Director Kenneth Melson, who has accused the U.S. Justice Department of attempting to shield its political appointees from implication in the scandal by withholding key information from congressional officials.

In a July 4 meeting between Melson and congressional investigators, of which details were released Monday, the ATF Acting Director claimed that the Justice Department was refusing to release a damning report, and other documents that implicate high-level officials in the scandal.

Tracy Schmaler, a Justice Department spokeswoman, rejected Melson’s allegations, saying “Any notion that the department has failed to cooperate with the investigation is simply not based in fact.”

Meanwhile, the family of U.S. immigration agent Jaime Zapata, who was murdered in Mexico in February, have demanded to know whether the weapons used in the agent’s death were among those which entered Mexico under Fast and Furious.