Photographs of the bodies showed them handcuffed, bloodied and bruised, some marked with a "Z'' on their torsos. Veracruz State Attorney General Reynaldo Escobar Perez told MVS radio Wednesday that they had been dead only a few hours.
Escobar, who earlier reported that many of the victims had links to organized crime, said they had records for kidnapping, extortion, murder and drug dealing. He called the killings unprecedented in a state where crime has been escalating dramatically, including deadly attacks on soldiers and journalists.
"The killing of 35 people is deplorable, but it's even more deplorable the same victims chose to extort, kidnap and kill," Veracruz Gov. Javier Duarte wrote via Twitter.
Authorities said they were examining surveillance video for clues to who left the 35 bodies beneath an overpass while other gunmen pointed weapons at frightened drivers.
Stunned motorists grabbed cellphones and sent Twitter messages warning others to avoid the area, which was alongside the biggest shopping mall in Boca del Rio, part of the metropolitan area of Veracruz city and less than a mile (1 kilometer) from where Mexico's top state and federal prosecutors and judiciary officials began a meeting Wednesday.
The bodies were left piled in two trucks and on the ground near the statue of the Voladores de Papantla, ritual dancers from Veracruz state.
Among the bodies was a local police officer who had disappeared two weeks ago, Escobar told W Radio in Mexico City.
Drug violence has claimed more than 35,000 lives across Mexico since 2006, according to government figures. Others put the number at more than 40,000.
The Gulf Cartel and the Zetas broke apart over the killing of a Zeta in the border city of Reynosa, across from McAllen, Texas, in January 2010. They have made a war zone of northeastern Mexico, drawing heavy presence of military and federal police in a special operation to stop the violence.
Since then, Zetas from the Mexico border area have been showing up in Veracruz, the U.S. official said.
Under Guzman, Sinaloa has grown bloodier and more powerful, controlling cocaine trafficking on the Mexican border with California, while expanding eastward to the corridor between Sonora and Arizona and waging a fierce battle for Chihuahua state bordering Texas.
Mexico's most powerful drug cartel also appears to be expanding methamphetamine production on a huge scale, but has not been known to operate along the Gulf of Mexico coast.
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