Mexican drug cartels have expanded the scope of their U.S. operations over 300 percent in two years, from operating in at least 230 cities in 2008 to more than 1,000 cities in 2010, according to a comparison of the U.S. Justice Department’s National Drug Threat Assessments.

“Law enforcement reporting indicates that Mexican Drug Trafficking Organizations (DTOs) maintain drug distribution networks or supply drugs to distributors in at least 230 U.S. cities,” said DOJ’s 2009 report, which contains data on the presence of Mexican DTOs from January 1, 2006, through September 30, 2008.

“Mexican drug traffickers transport multi-ton quantities of drugs from Mexico into the United States annually using overland, maritime, and air conveyances.”

DOJ’s 2011 report found that Mexican-based transnational criminal organizations (TCOs) — the new term the department uses in the report for DTOs — were “operating in more than a thousand U.S. cities during 2009 and 2010, spanning all nine Organized Crime Drug Enforcement Task Force (OCDETF) regions.”

Furthermore, the National Drug Intelligence Center (NDIC) assesses with “high confidence” that Mexican-based TCOs “control distribution of most of the heroin, marijuana, and methamphetamine available in the United States,” and production of these drugs in Mexico “appears to be increasing.”

The primary regions where the TCOs have been operating are Florida/Caribbean, Great Lakes, Mid-Atlantic, New England, New York/New Jersey, Pacific, Southeast, Southwest and West Central. (RELATED: DOJ says Mexican cartels operating in over 1,000 U.S. cities)

The 2011 report also declares the cartels “control” the U.S.-Mexico border.

“Mexican-based trafficking organizations control access to the U.S.–Mexico border, the primary gateway for moving the bulk of illicit drugs into the United States,” according to the report.

“The organizations control, simultaneously use, or are competing for control of various smuggling corridors that they use to regulate drug flow across the border.”

On February 15, 2011, Richard M. Stana, the director of Homeland Security and Justice at the Government Accountability Office testified before the House Subcommittee on Border and Maritime Security about the state of security on the southwest border.

“Our analysis of the 873 border miles under operational control, reported by Border Patrol in fiscal year 2010, showed that about 129 miles — or 15 percent — were classified as “controlled,” which is the highest sustainable level for both detection and interdiction at the immediate border,” he said in his opening remarks.

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