(CNN) -- Mexico's president called on U.S. officials to stop gun trafficking across the border Thursday, saying the move would be the best thing Americans could do to stop brutal drug violence. "The criminals have become more and more vicious in their eagerness to spark fear and anxiety in society," President Felipe Calderon said. "One of the main factors that allows criminals to strengthen themselves is the unlimited access to high-powered weapons, which are sold freely, and also indiscriminately, in the United States of America." Speaking in Ciudad Juarez, the border city across from El Paso, Texas, that has become Mexico's murder capital, Calderon said a dramatic increase in violence in Mexico was directly connected with the 2004 expiration of the U.S. assault weapons ban.
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Calderon says criminals have "unlimited access to high-powered weapons"
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He stands before a new sign in Ciudad Juarez that says, "NO MORE WEAPONS"
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The president says Mexico needs U.S. help to stop the violence
During his Thursday speech, Calderon looked toward the border and said he had a message for @placeholder.