Investigators linked the weapons sent to violent Mexican cartels by the Obama administration's Fast and Furious gun-running program to dozens of deaths.

The sting operation was supposed to follow the weapons to their destinations, but authorities quickly lost sight of most of them.

Judicial Watch found the weapons were linked to 69 deaths, including a massacre in which 22 died. That's in addition to the gun that was used to kill Border Patrol Agent Brian Terry in a 2010 firefight with Mexican bandits.

Now investigative reporter Sharyl Attkisson says another Fast and Furious weapon has been found.

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It was in the hands of violent armed groups in Chihuahua, Mexico.

Mexican police and military arrested nine people and confiscated 10 weapons on June 20 after a gunfight between two groups, she reported. One of the weapons, a semi-automatic rifle, traces back to Fast and Furious.

It was a Romarm Cugir GP-WASR 10/63 rifle.

According to a police report, the serial number was traced to a weapon sold in Prescott, Arizona, to Fast and Furious suspect Sean Steward in 2009.

"Steward eventually pled guilty to trafficking firearms while the Bureau of Alcohol, Tobacco and Firearms was monitoring him under Operation Fast and Furious," she reported.

The operation was a so-called "gunwalking" strategy in which the federal government during 2009-2011 put thousands of assault rifles and other weapons into the hands of Mexican drug cartels.

Terry and Immigration and Customs Enforcement agent Jaime Zapata were killed by cartel thugs in two separate attacks in 2010 and 2011. Both cases were "related to guns that were trafficked while under the watch of U.S. agents who neither intervened nor tracked the 'walked' weapons," the report said.

Bureau of Alcohol, Tobacco and Firearms officials at the time lamented the "homicides or murders that have been caused by the firearms that we allowed to be trafficked."

Attkisson said that since 2011, the Justice Department has "refused repeated requests from Congress and the news media to fully disclose details of incidents involving guns that had been illegally trafficked to Mexican drug cartels under the watch of U.S. agents in Operation Fast and Furious."

Judicial Watch said that between December 2012 and March 2014, 94 Fast and Furious weapons were seized, including one found in the hideout of drug lord "Chapo" Guzman.

That included 82 rifles and 12 handguns.