In this Wednesday, Dec. 15, 2010 picture, an American flag on a resident's home waves in the breeze near a U.S. Border Patrol truck blocking the road leading to a search area near where U.S. Border Patrol agent Brian Terry was killed northwest of Nogales, Ariz. (AP Photo/Arizona Daily Star, Greg Bryan)

(CNSNews.com) – An alleged Mexican drug trafficker awaiting trial in a Chicago federal court claims that the notorious Sinaloa cartel received weapons from “Operation Fast and Furious” under an alleged immunity agreement that the U.S. government made with cartel leaders, in exchange for information on rival gangs.

The defendant in a trafficking case before the U.S. District Court for the Northern District of Illinois, Vicente Jesus Zambada-Niebla, also claims the immunity deal allowed the criminal cartel to “continue to smuggle tons of illicit drugs” into the United States.

He wants the U.S. government to provide documents relating to the botched gun running sting operation along the southwest border, arguing that it would benefit his defense.

Operation Fast and Furious, which began in September 2009, saw the Phoenix office of the Bureau of Alcohol Tobacco, Firearms and Explosives supervise the sale of guns to straw purchasers with the intent of tracing the guns to Mexican drug trafficking organizations and prosecuting their members. The ATF allowed about 2,000 guns to be sold in this manner.

The operation came under congressional scrutiny after it was linked to the December 2010 murder of U.S. Border Patrol agent Brian Terry at the hands of Mexican bandits.

An investigative report, spearheaded by Rep. Darrell Issa (R-Calif.) and Sen. Chuck Grassley (R-Iowa), found that most of the weapons provided to Mexican criminals under the operation were going to the Sinaloa cartel, arguably one of the world’s largest drug trafficking organizations.

In a court pleading filed last July, Zambada-Niebla made the claims about an immunity deal.

“Mr. Zambada-Niebla believes that the documentation that he requests will confirm that the weapons received by Sinaloa Cartel members and its leaders in Operation ‘Fast & Furious’ were provided under the agreement entered into between the United States government and [a Mexican lawyer] on behalf of the Sinaloa Cartel that is the subject of his defense …,” it said.

“Mr. Zambada-Niebla believes that the documentation will also provide evidence showing that the United States government has a policy and pattern of providing benefits, including immunity, to cartel leaders, including the Sinaloa Cartel and their members, who are willing to provide information against rival drug cartels.”

The defendant argued that he is protected from federal prosecution for trafficking drugs into the U.S. between 2004 and 2009 under an alleged immunity deal struck between the U.S. government and Sinaloa leaders.

According to court documents, Zambada-Niebla claims that the immunity deal provided the cartel’s leadership with “carte blanche to continue to smuggle tons of illicit drugs into Chicago and the rest of the United States” in exchange for information on rival drug cartels.

U.S. prosecutors deny the existence of such an immunity deal between the U.S. government and the cartel.

Nevertheless, the U.S. government last September filed a motion to invoke the Classified Information Procedures Act, which is aimed at assuring that national security information stemming from criminal cases – such as details associated with CIA operations – are not leaked to the public during court proceedings.

In a court pleading filed in September, U.S. prosecutors claimed that Zambada-Niebla’s allegations about Fast and Furious have no merit.

“Defendant requests all information in the possession of the U.S. government related to an ATF investigation referred to as ‘Fast and Furious’…” it said. “Defendants request related to Fast and Furious … and other unrelated matters are gratuitous and wholly unrelated to any legitimate discovery issues in this case.”

Zambada-Niebla, who was arrested in Mexico in March 2009 and extradited to the U.S. eleven months later, is accused of smuggling tons of cocaine and heroin into the U.S.

He claims he was working on behalf of the U.S. Department of Justice, Drug Enforcement Administration, FBI, and U.S. Immigrations and Customs Enforcement, court documents show.

The defendant’s pleading highlighted a July 2011 letter sent by Issa and Grassley to Attorney General Eric Holder, “suggesting that multiple United States agencies were employing as informants members of Mexican drug organizations.”

“The evidence seems to indicate that the Justice Department not only allowed criminals to smuggle weapons, but that tax payers’ dollars in the form of informant payments, may have financed those engaging in such activities,” the pleading added.