MEXICO CITY — Drug lord Joaquin “El Chapo” Guzman purportedly has come gunning for the vicious Zetas gang on the South Texas border, leaving 14 of their butchered bodies and a message vowing to rid Nuevo Laredo of its criminal scourge as a calling card.

“We have begun to clear Nuevo Laredo of Zetas because we want a free city and so you can live in peace,” proclaims a banner, under which were posed the bodies, as well as the gunmen presumably in Guzman’s employ. “We are narcotics traffickers and we don’t mess with honest working or business people.”

Guzman’s first attempt to seize Nuevo Laredo, bordering Laredo, in 2005 sparked a gangland war with the Zetas and their then-paymasters in the Gulf Cartel. The battles, complete with rocket attacks and massacres, killed more than 300 that year and gave birth to the hyper-violence still tormenting the borderlands and Mexico’s interior.

The Zetas and the Gulf Cartel won that earlier contest. Now Guzman, one of the most wanted men in the hemisphere, looks to be back.

This time he’s presenting himself as a White Knight, succeeding where Mexico’s military and federal police so far have failed in defeating the Zetas and restoring order.

“I’m going to teach these scum to work Sinaloa style,” the banner purportedly signed by Guzman sneers, “without kidnapping, without payoffs, without extortion.”

“As for you, 40,” the banner says, addressing Zetas boss Miguel Treviño by his code name Z-40. “I tell you that you don’t scare me.”

‘Your true father’

The message also warns Nuevo Laredo’s citizens that anyone who continues paying extortion money to the Zetas would be considered “a traitor.”

“Don’t forget that I’m your true father,” the banner advises.

Photos of the mangled corpses first appeared Wednesday on Blog del Narco (www.blogdelnarco.com), a website that posts up-to-date crime news in Mexico, and came a day after the 14 bodies were discovered stuffed into a minivan parked near Nuevo Laredo’s city hall. A note left with the bodies declared the victims “traitors.”

The authenticity of the photos in the post, or the source of the threats it contains, couldn’t be verified. A similar post on another blog in late March included photos of detached human arms and a handwritten message, supposedly from Guzman, also threatening Zetas bosses and claiming that all of Tamaulipas state, including Nuevo Laredo, belonged to the Sinaloa Cartel.

“Chapo is going to step up to the plate and become the protector of the poor people against the Zetas,” predicted Mike Vigil, retired chief of international operations for the Drug Enforcement Administration. “Obviously it is a vested interest because it behooves him and the other cartels to get rid of the Zetas that are causing a lot of problems for them.”

Laredo taking action

Vigil is a consultant in Mexico and in regular contact with senior government officials there.

Officials in Laredo are watching closely. “There is continued concern, but we have dedicated all the resources necessary to ensure we don’t have a spillover on the Laredo side,” said Laredo Mayor Raul Salinas, a retired FBI agent. “Obviously any time we have a situation like this – and other cities on the border would react the same way – we monitor very carefully what happens on the other side of the river.”

Listed by Forbes as one of the world’s wealthiest men, Guzman is arguably Mexico’s most powerful crime boss. Though widely considered an old-school narcotics trafficker who generally has left civilians in peace, Guzman has been blamed for a number of atrocities.

The Sinaloan’s four-year struggle for Ciudad Juarez, bordering El Paso, has been blamed for nearly 10,000 murders. Some have credited Juarez’s nearly 40 percent decline in murders in recent months to Guzman’s reported victory in that battle.

“The Zetas are trying to take over the country and they are a tremendous force to be reckoned with,” Vigil said. “It is a situation of fighting fire with fire and I think that you are going to see much more of that as the cartels engage them.”

dudley.althaus@chron.com

dane.schiller@chron.com