WASHINGTON – The ultra-violent, U.S.-trained elite, Mexican paramilitary commandos known as the “Zetas,” responsible for hundreds of murders along the border this year, have expanded their enforcement efforts on behalf of a drug cartel by setting up trafficking routes in six U.S. states.

A U.S. Justice Department memo says the U.S.-trained units have recently moved operations into Houston, San Antonio and the states of California, Oklahoma, Tennessee, Georgia and Florida. They have been operating in Dallas for at least two years, according to the feds.

The original Zetas are former Mexican army commandos, some apparently trained in the U.S. by Army special forces to combat drug gangs. Members of a broader Zetas organization have worked for the Gulf cartel since 2001. They provide firepower, security and the force needed to oversee shipments of narcotics and smuggled aliens along the border and up Interstate 35, which runs through Texas and Oklahoma.

According to FBI officials, the Zetas are attempting to consolidate their grip on the smuggling route along I-35. Anyone caught not paying the 10 percent commission they charge on all cargo – drugs or humans – is killed, according to U.S. and Mexican law enforcement sources.

The Zetas have also brought their cold-blooded killing tactics to the U.S., say federal law enforcement authorities – murdering rival drug dealers and sometimes innocent bystanders.

“Texas law enforcement officials report that the Zetas have been active in the Dallas area since 2003,” said the Justice Department intelligence bulletin circulated among U.S. law enforcement officials. “Eight to ten members of the Zetas have been involved in multiple assaults and are believed to have hired criminal gangs in the area … for contract killings.”

The feds say the group has begun establishing its own trafficking routes into the United States and will protect them at any cost.

“U.S. law enforcement have reported bounties offered by Los Zetas of between $30,000 and $50,000 for the killing of Border Patrol agents and other law enforcement officers,” the bulletin said. “If a Zeta kills an American law enforcement officer and can successfully make it back to Mexico, his stature within the organization will be increased dramatically.”

The Zetas take their name from a radio code once used by its members. While originally there were 68, the Zetas have trained a second generation of commandos – many of them sons and nephews of those trained by U.S. military forces to combat drug trafficking in Mexico. U.S. law enforcement officials say they now number more than 700. Their numbers also include some Mexican army deserters and former federal police officers.

U.S. and Mexican law enforcement authorities say the Zetas operate special training camps in the Mexican states of Tamaulipas and Michoac?n, where newly recruited Zetas take intensive six-week training courses in weapons, tactics and intelligence gathering.

The Zetas conducting a bloody war for control of the entire southern border in an effort to secure a monopoly on drug-smuggling and people-smuggling routes, according to law enforcement officials.

At least 600 have been killed this year in a wave of violence waged by the Zetas gang, headed by reputed drug kingpin Joaquin “El Chapo” Guzman, said Mexico’s Attorney General Daniel Cabeza de Vaca.

Among the victims of the U.S-trained Zetas have been other suspected smugglers, hit men, police, soldiers and civilians on both sides of the 2,000-mile border.

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

The U.S. government 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.

Guzman, whose nickname means “Shorty,” bribed guards to escape from prison in 2001. He is one of Mexico’s most-wanted fugitives. U.S. authorities have offered a $5 million reward for his capture.

The spike in killings and kidnappings in northern Mexico in recent months has made headlines and prompted federal agents and soldiers to patrol the streets of Nuevo Laredo, across from Laredo, Texas. Recently, a new police chief in Nuevo Laredo was assassinated nine hours after taking office.

Among the 600 people murdered in gang shootings across the Mexican border this year, many were slain execution-style, with their hands tied behind their backs.

The violence along the border has reached a point where some are questioning President Vicente Fox’s ability to govern the country.

A senior U.S. Drug Enforcement Administration official, Anthony Placido, told Congress last week that Mexico’s corrupt police forces were “all too often part of the problem rather than part of the solution” in fighting the drug cartels.

Fox won office in 2000, ending 71 years of one-party rule and promising to clamp down on the multibillion-dollar cross-border trade in cocaine, marijuana and heroin.

While initially winning praise for putting bosses like Benjamin Arellano Felix and Osiel Cardenas behind bars, his crime-busting reputation has been undermined by the alarming rise in violence, along with evidence Fox has failed to clean up Mexico’s police forces.

Faced with the fallout on its southern frontier, the State Department has twice issued travel warnings for the Mexican border, where more than 30 U.S. citizens have been kidnapped.

Mexico’s apparent inability to curb the bloodshed on the 2,000-mile border is affecting the financial markets. Banking group HSBC said “staggering” levels of violence could raise questions about Mexico’s stability in the run-up to next year’s presidential election. Fox is constitutionally barred from running for re-election.

His approval rating has taken a hit, dropping 3 points to 56 percent in a poll in May, with many Mexicans complaining of safety fears, particularly in the north.

Fox has pledged a “mother of all battles” against the drug traffickers he says are openly challenging the government.

“We have taken on the challenge and we will do battle against all the cartels’ criminals and against organized crime,” Fox said in a speech Friday.

He sent hundreds of troops and federal agents to the states of Tamaulipas, Sinaloa and Baja California last week after suspected drug hit men killed the police chief of Nuevo Laredo.

Despite the move, drug gangs shot and killed at least 11 people across the three states during the week, prompting observers to declare the operation, dubbed “Mexico Secure,” a failure.

Previous stories:

Mexico drug war result of NAFTA?

It’s war between cops in Mexico

Police chief murdered on 1st day

The threat from Mexico

‘It’s a war’ along Mexican border

Mexican commandos seek control of border

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