A Mexican police officer works next to a pickup with the body of a policewoman, in the Mozimba neigborhood of Acapulco, Guerrero state, Mexico on August 17, 2012. Acapulco is one of Mexico's most popular seaside resorts. More than 50,000 people have been killed after President Felipe Calderon launched a crackdown on the drug cartels in December 2006. AFP PHOTO/Pedro PARDO (Photo credit should read Pedro PARDO/AFP/GettyImages) A Mexican police officer works next to a pickup with the body of a policewoman, in the Mozimba neigborhood of Acapulco, Guerrero state, Mexico on Aug. 17, 2012. (credit: Pedro PARDO/AFP/Getty Images)

WASHINGTON (CBSDC) — A gun found at the scene of a shootout between a Mexican drug cartel and soldiers where a beauty queen died was part of the botched “Fast and Furious” operation, CBS News reports.

Authorities had said that Maria Susana Flores Gamez was likely used as a human shield and that an automatic rifle had been found near her body after the Nov. 23 shootout.

Sen. Chuck Grassley, R-Iowa, tells CBS News that the Justice Department did not notify Congress that a Fast and Furious firearm was found at the scene in Sinaloa.

CBS News learned the Romanian AK-47-type WASR-10 rifle found near her body was purchased by Uriel Patino at an Arizona gun shop in 2010. Patino is a suspect who allegedly purchased 700 guns while under the ATF’s watch.

The “Fast and Furious” operation was launched in 2009 to catch trafficking kingpins, but agents lost track of about 1,400 of the more than 2,000 weapons involved.

Authorities say the ring was believed to have supplied the Sinaloa cartel with guns. Mexico’s drug cartels often seek out guns in the U.S. because gun laws in Mexico are more restrictive than in the U.S.

Some guns purchased by the ring were later found at crime scenes in Mexico and the United States.

The operation came to light after Border Patrol Agent Brian Terry was killed in December 2010 by marijuana smugglers who used guns from the “Fast and Furious” operation.

Federal authorities who conducted the operations have faced tough criticism for allowing suspected straw gun buyers for a smuggling ring to walk away from gun shops in Arizona with weapons, rather than arrest them and seize the guns.

Several Republicans have called for the resignation of Attorney General Eric Holder due to the botched operation.

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