Bodies are piling up along U.S.-Mexico border towns as two formerly allied drug gangs engage in open combat in Mexico’s streets within miles of U.S. cities – but the cartels’ empires are hardly limited to the south side of the border.

Two drug gangs in the town of Reynosa, across from McAllen, Texas, are fighting to gain control of key drug routes. A 200-mile stretch of border from Matamoros to Nuevo Laredo – directly across from Brownsville to Laredo, Texas – is brimming with violence stemming from bloody battles between the long-established Gulf Cartel and a group called Los Zetas, former Mexican special-forces soldiers originally recruited as assassins for the Gulf Cartel.

The U.S. government has called Los Zetas “the most technologically advanced, sophisticated and dangerous cartel operating in Mexico.”

Ralph Reyes, the U.S. Drug Enforcement Agency’s chief for Mexico and Central America, explained in August, “The Zetas have obviously assumed the role of being the No. 1 organization responsible for the majority of the homicides, the narcotic-related homicides, the beheadings, the kidnappings, the extortions that take place in Mexico.”

Los Zetas’ recruitment campaigns have been highly visible and include the use of public narco banners posted around Mexico, promising servicemen better pay and benefits than the military offers.

Los Zetas is known for displaying recruitment banners geared toward current and former military members.

Meanwhile, hit men from the Gulf Cartel are paying reporters about $500 a month and providing them with liquor and prostitutes to bribe them to work as spies and suppress coverage of killing sprees on the U.S. border, Reuters reported.

According to the report, at least 100 deaths in Reynosa during the last three weeks have remained largely unreported due to the media blackout.

“Our newsrooms have been infiltrated by these reporters. They monitor what we write. They know where we live. With this system, the narcos have direct control over us,” said a local newspaper editor.

Also, eight journalists were kidnapped in Reynosa between Feb. 18 and March 3, according to Inter-American Press Association reports. One was discovered dead. Two were released alive, and five are missing.

Reynosa residents are using social-networking sites such as Facebook, Twitter and YouTube to post videos of shootouts and report suspicious activity, Reuters reported.

Drug gangs have established vehicle checkpoints along highways to the U.S. border as they search for members of rival gangs. The Gulf Cartel and Los Zetas are only two of at least seven powerful Mexican drug cartels. The following is a National Drug Intelligence Center map of the general regions in Mexico controlled by drug cartels:

2007 Congressional Research Service report for Congress provides this map of Mexico regions controlled by drug cartels (prior to Gulf Cartel and Los Zetas split).

According to a 2007 Congressional Research Service report for Congress, Mexican cartels are “starting to show the hallmarks of organized crime, such as organizing into distinct cells with subordinate cells that operate throughout the United States.”

In 2009 the U.S. Department of Justice National Drug Intelligence
Center identified about 200 major U.S. cities with known presence
of Mexican drug-trafficking organizations. The following is a map of
those cities:

The drug cartels produce and distribute methamphetamine and marijuana in the U.S.

“There is evidence that Mexican cartels are also increasing their relationships with prison and street gangs in the United States in order to facilitate drug trafficking within the United States as well as wholesale and retail distribution of the drugs,” CRS reported.

In addition to drug trafficking, the Mexican cartels have been tied to incidents of human trafficking, auto theft and kidnapping. An estimated 18,000 people have been killed in Mexico’s drug violence in the last three years.

The fresh surge of bloodshed comes on the heels of President Obama’s reiteration of his “unwavering” commitment to comprehensive immigration reform in recent days.

Sens. Charles E. Schumer, D-N.Y., and Lindsey Graham, R-S.C., have presented Obama with a three-page blueprint to overhaul the immigration system.

According to the Los Angeles Times, the plan includes proposals for a temporary-worker program and biometric Social Security card.

Graham said the proposal includes “a rational plan to deal with the millions of illegal immigrants already in the United States.”

“We’re not going to mass-deport people and put them in jail, nor should we,” Graham said in a recent interview. “But we need a system so they don’t get an advantage over others for citizenship.”

Graham added that Obama must also deal with “virtual fences” on the U.S.-Mexican border. He said the fences have “proven much more complex and difficult to implement than originally expected.”

“The administration must make this a priority as securing our borders is a confidence-building measure in the eyes of the American people,” Graham said.

President Obama’s 2011 budget slashes funding for border-security programs. According to USA Today, the “virtual” fence of pole cameras and sensors aimed at stopping illegal aliens, drug smugglers and terrorists on the U.S.-Mexican border is facing a $225 million cut from $800 million last year. While 643 miles of existing concrete-and-steel border fence will be maintained, no funding is included for new barriers to be built.

While the battles rage just across the border and within miles of U.S. cities, one Texas sheriff spotted a Mexican military helicopter hovering over a residential neighborhood on the Texas side of the Rio Grande last week. The flight was an unauthorized incursion into the United States.

The sheriff said the helicopter featured the insignia of the Mexican navy and flew more than a mile over the border for at least 20 minutes. Witnesses said the helicopter had armed men inside and the cargo ramp down.

Texas Gov. Rick Perry released a statement today about the incursion.

“The helicopter incursion and uptick in violence in Mexican border communities underscore the urgent need for more U.S. law enforcement and surveillance along the Texas-Mexico border,” he said. “I once again urge our federal government to add personnel and technology along the Texas-Mexico border to prevent spillover violence here and to combat drug cartels operating in the border region.”

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