Mexico has long complained that drug gangs are terrorizing cities with high-powered weapons smuggled from the United States. But Mexican lawmakers are now up in arms over the recent revelation that the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) purposefully allows some of these weapons to be smuggled south of the border so it can track them as part of “Operation Fast and Furious.” One senior Mexican lawmaker called the operation “a grave violation of international rights.”

Laura Carlsen is director of the Americas Program of the Center for International Policy and a columnist for Foreign Policy in Focus. She’s based in Mexico City and has been following the latest scandal in the Mexican Drug War.