Jean Baptiste Kingery

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Prosecutors allowed grenade parts to flow across the border with Mexico, according to a new IG report

Mexican and U.S. authorities planned a sting, but lost track of the suspect who sold the grenade parts

Grenade hulls were used in violent attacks by Mexican cartels, but are available in the U.S. in military supply stores

Washington CNN  — 

An American trafficked thousands of grenade components to Mexico, many of which turned up in hands of drug cartel who used them in violent attacks, and federal agents were prevented from stopping it, in part because federal prosecutors wouldn’t bring charges.

Those are the finding of a new Justice Department inspector general report to be released Thursday. It harshly criticizes prosecutors in the Phoenix U.S. attorney’s office and agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives.

Read the DOJ Inspector General’s report

The report cites some of the same officials who were part of the botched Operation Fast and Furious, which allowed suspected arms traffickers to buy thousands of firearms, many of which ended up used in cartel violence.

Jean Baptiste Kingery, an American from Arizona, was the suspect in the grenades case. He was arrested in 2011, in Mexico and has been charged with violating that nation’s organized-crime laws.

Related: ATF probes ties between grenade in Mexico and American

Authorities then found his alleged grenade factory where they discovered parts that could have been used to manufacture about a 1,000 grenades.

But that arrest only came months after ATF agents tried several times to arrest him, only to have prosecutors refuse to bring charges, according to the IG report and documents reviewed by CNN but not included in the report. Prosecutors argued that possessing hundreds of grenade hulls, commonly sold in U.S. military surplus stores as novelties, weren’t necessarily a crime.

Unlike, Fast and Furious, agents in the Kingery case worked with Mexican law enforcement to try to conduct a sting operation to stop Kingery. But Mexican officers missed him and he managed to get across the border with his cargo of grenade hulls.

The Justice Department said in a statement: “In the six years since this operation was begun, we have taken aggressive action to ensure these errors are not repeated. The department does not condone the conduct that occurred during this investigation, and those individuals identified by the report as responsible for the operation have either been reassigned or left the department.”

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