More Fast and Furious Weapons Show Up at Violent Crime Scenes in Mexico

A month ago, Republican Senator Chuck Grassley sent a letter to Attorney General Eric Holder asking why the Department of Justice was covering up deaths and weapons linked to Operation Fast and Furious. The inquiry came shortly after a Mexican police chief and his body guard were killed by cartel members using Fast and Furious guns.

"Since the beginning of this investigation, we have followed the link between Fast and Furious weapons and crimes committed on both sides of the border. On numerous occasions we have asked the Department to keep us apprised of Fast and Furious weapon recoveries -- especially as they relate to violent crimes," Grassley wrote. "Despite our repeated requests, it has been over a year since we last heard from the Department on this issue. The Department his from Congress this recent internal trace record showing a link between the murder of a police chief and Fast and Furious. Such actions do little to promote trust between the Department and Congress, and only provide further evidence that the Department is actively trying to conceal all information pertaining to Fast and Furious from Congress."

Now, CBS News' Sharyl Attkisson has learned of more Fast and Furious guns surfacing at crime scenes in Mexico.

Three more weapons from Fast and Furious have turned up at crime scenes in Mexico, CBS News has learned, as the toll from the controversial federal operation grows.

According to Justice Department tracing documents obtained by CBS News, all three guns are WASR-10 762-caliber Romanian rifles. Two were purchased by Fast and Furious suspect Uriel Patino in May and July of 2010. Sean Steward, who was convicted on gun charges in July 2012, purchased a third. The rifles were traced yesterday to the Lone Wolf gun shop in Glendale, Ariz.

During the course of Operation Fast and Furious from 2009-2010, 2500 weapons were purchased by illegal straw buyers under ATF surveillance in the United States and trafficked into Mexico. At least 1400 of those weapons are still missing. The only way ATF can recover these weapons is when they are left at crime scenes.

The consequences of Fast and Furious have been lethal. In December 2010, Border Patrol Agent Brian Terry was murdered in Arizona's Peck Canyon and weapons from the operation were left at the scene. In 2011, ICE Agent Jaime Zapata was killed in Mexico by cartel members using weapons purchased by buyers under ATF surveillance. In 2012, Mexican beauty queen Susana Flores Gamez and four others were killed, Fast and Furious weapons were found at the crime scene.

Attorney General Eric Holder is still in criminal and civil contempt of Congress. The House Oversight Committee is currently in a court battle with the Department of Justice over documents surrounding the operation and President Obama's assertion of executive privilege over documents in June 2012.