The Washington Post carried a full story today (full article here):
According to authors Colby Goodman and Michel Marizco, at least 62,800 of the more than 80,000 firearms confiscated by Mexican authorities from December 2006 to February 2010 came from the United States. Guns are being smuggled across the border at a rate of up to 5,000 per year. The top two varieties are assault rifles: Romanian-made AK47s and clones of the Bushmaster AR-15. More than 2,000 police and federal agents are among the 28,000 killed in drug-related violence in the past four years. According to Mr. Goodman and Mr. Marizco, whose work was sponsored by the Woodrow Wilson Center and the University of San Diego, just one gun store in Houston supplied 339 assault weapons, rifles and pistols to cartel buyers in just 15 months -- which were responsible for the deaths of 18 Mexican law enforcement officers and civilians.