Each morning for six months, the 87 cadets of the Ciudad Juárez Municipal Police Department proudly stand at attention knowing that when they graduate and start patrolling the streets of their violent city, there is a good chance they will be gunned down by an old foe with a new identity.

Since Julian Leyzaola took over as police chief in March 2011, the murder rate has plummeted, signaling a new era in what has been called "The Murder Capital of the World." But as a result of many new and aggressive strategies, his department has been targeted. Twenty officers have been killed so far this year and 63 since Juárez Mayor Mator Héctor Murguía took office in October 2010.

These delinquents are beasts and we will catch them. Chief Leyzaola said he is not resigning and we don't expect him to.

- Hector Murguia, Mayor of Ciudad Juárez

In January, mantas [banners], began appearing around the city, calling for Leyzaola to resign, and if not, one of his officers would be killed each day. The threats were attributed to the New Juárez Cartel. 

After a flurry of fatal ambushes shortly after the mantas began appearing, police were given the opportunity to stay in secure motels and carry their service weapons off duty, a policy implemented in response to the wave of police murders.

Leyzaola has stood defiant against the targeted murders, unlike his predecessor who resigned in 2009 after a similar assassination wave spread throughout the city. Roberto Orduña Cruz, the former chief, said at the time he was resigning because he didn't want to risk the lives of any more officers.

The current administration sees resignation as admitting defeat. The murder of police officers has subsided since 2009 but the threat remains high.

"These delinquents are beasts and we will catch them," the Juárez mayor said. "Chief Leyzaola said he is not resigning and we don't expect him to."

Murguía said that new policies, such as establishing patrol districts and more community-type policing, has contributed dramatically to the decrease in murders. Murders hit a high of 3,075 in 2010, followed by a drop to 2,015 in 2011. In the first quarter of 2012, there were 270 murders compared to 710 during the same period in 2011.

"Morale is higher than it has been in years because Leyzaola is a hands-on manager," said one eight-year police veteran who only wanted to be identified as Patrolman Francisco. "We are much more professional and getting results."

Officials believe this reborn police effort has been a source of antagonism among many of the mid and lower level street gangs, one of which is La Linea, identified by law enforcement officials as the notorious enforcement arm of the Vicente Carillo Fuentes Juárez Cartel. 

The group has contributed to the more than 12,000 killed in the city fighting against elements of El Chapo Guzman's Sinaloa Cartel, which has established a foothold in Juárez as well as street-level entrepreneur drug dealers selling their products without paying the appropriate tax to the cartel. They have also been involved on a major scale in extortion and kidnapping.

U.S. federal law enforcement officials said the New Juárez Cartel is not a new group but actually an image makeover of La Linea. Their presence was first made public on Sept. 26, 2011 in a YouTube video released by NCJ -by their acronym in Spanish- of black clad men with the three initials of the group emblazoned in white on the black paramilitary uniforms interrogating  a captured prison guard who claimed he and other guards of Cereso Prison in Juárez worked for the Sinaloans

"The speculation is that they felt their name was 'tainted', if you will, because they had brought so much attention to themselves because of their acts of violence and so law enforcement was and is really looking at them," said a federal agent who asked not to be identified. "We do not believe their role has changed and it is speculated that they are responsible for the police killings."

In January, at the height of the police murders, Leyzaola announced that Johnny “El Tin Tan” Morales González, a member of the New Juárez Cartel, was responsible for recent attacks on the city’s police force.

As far as U.S. law enforcement, intelligence of New Juárez Cartel is unfolding.

"We do not have any information that Johnny Morales is 'Tin Tan'," said the agent. "As far as who is the head we are not sure of the structure of the NCJ since there have been several high profile arrests by Mexico in the past few months."

Juxtaposed against this mounting evidence Murguía retracted his position of the existence of the New Juárez Cartel and said Leyzoala erroneously made the statement that they existed.

"That was a misunderstanding, it was a mistake," Murguía said.

The U.S. federal agent said the gist of the information they have is that although it’s a new name they are using, La Linea is essentially the same organization.

"The relationship is the same as far as we know that they are still the enforcement arm of the VCF cartel," said the federal agent.

Joseph J. Kolb is a regular contributor to Fox News Latino.

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