Mexican drug gangs like the Gulf cartel and the Sinaloa alliance are armed with AR-15 assault rifles and AK-47s bought legally in the United States

Mexican drug gangs like the Gulf cartel and the Sinaloa alliance are armed with AR-15 assault rifles and AK-47s bought legally in the United States and smuggled into Mexico."Ninety-five percent of the weapons (in Mexico) come from the United States," said Aldo Fasci, police chief of northern Mexico's Nuevo Leon state, where the Gulf cartel is active. "The drugs are there and the violence is here in Mexico, and it is permeating the border with the United States."Mexican military officials and federal police say corruption is a major problem at Mexico's border posts, with officials taking bribes to wave weapons and drug cash through.In the United States, several Customs and Border Protection agents were arrested last year and accused of taking money from drug gangs to turn a blind eye to smuggling.Drug cartels are also experts at avoiding detection of their goods and cash."If they know there is a particular search program in place in one port, they will immediately divert their efforts to smuggle arms into Mexico to a different port," said Arizona Attorney General Terry Goddard.