WASHINGTON – Elite Mexican commandos, trained by U.S. forces to combat the drug cartels have switched sides and are working for the drug smugglers in the border area posing a special hazard to American law enforcement and Border Patrol agents, according to a U.S. Justice Department memo.

The commandos, trained by the U.S. Army at Fort Benning, Ga., are known as “Los Zetas.”

The Justice Department warning was sent to law enforcement agencies throughout the Southwest.

Using the commando training, Los Zetas are known to be extremely violent and have been blamed for an outbreak of violence along the Mexican border.

There are reports of the commandos making cross-border runs into U.S. territory in military-style vehicles, armed with automatic weapons.

The U.S. government has spent millions of dollars training Los Zetas to intercept drugs, some of them coming from Mexico’s southern border, before they could reach the U.S. The U.S. government has also sent U.S. Border Patrol agents to Mexico’s southern border with Guatemala to train law enforcement and military forces to intercept human smugglers destined to reach the U.S.

“Things like that are a concern to us, especially trained here on the U.S. side,” Pima County Sheriff Tony Estrada told KVOA, channel 4 in Tucson, Arizona. “They’ve gotten pretty special training. … Now, they are working with drug traffickers on the Mexican side.”

Lt. Ron Benson added: “Not only did they receive some early military training but they developed their own internal training as well increasing their violence far beyond their own original capabilities.”

Benson has worked with the Department of Homeland Security and tracked the rogue Mexican commandos. He is now retiring from the Pima County Sheriff’s Department and will be working with the FBI.

“They are a threat to authorities not only in Texas, but in New Mexico, Arizona and California,” he said. “Because we believe Los Zetas are being used as protectors for narcotics coming into this country.”

Benson says sons and nephews of Los Zetas are starting their own organization and taking part in the drug wars.

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