The U.S. Consulate has issued a security alert for Nuevo Laredo after unofficial reports of at least 50 people killed in the past week.
Nine more bodies were reported found Friday morning at the same highway overpass where other bodies were hung in May. The alert also said the majority died in 12 separate incidents, including arson attacks.
"The danger to innocent bystanders is high," the alert said, urging U.S. citizens to keep a low profile and a heightened sense of awareness.
Referencing Mexican law enforcement sources, the alert also said, "The increase in violence is likely the result of a split with the Zeta leadership."
The alert said the violence may continue as the Zetas "attempt to settle scores and vie for control of Nuevo Laredo."
Also found along with bodies strewn above and below the overpass was a note that threatened the Gulf Cartel.
Its long time leader, Jorge Eduardo Costilla Sanchez, better known as "El Coss," was the Mexican government's latest arrest of high-ranking members of the Gulf Cartel in the past two weeks.
"He's one of the highest level traffickers that they've arrested in years," said Will Glaspy, assistant special agent in charge with the U.S. Drug Enforcement Administration in the Rio Grande Valley.
However, Glaspy said it's believed Costilla already had been pushed aside by conflicts with the Gulf Cartel, so violent power struggles could be doubtful.
"The people who would step up in the case of his arrest, have already done so," Glaspy said.
But he said it is still too early to say whether the Zetas, the Gulf Cartel's arch-rivals and one-time enforcers, will try to seize even more power.
Glaspy said the Gulf Cartel already had aligned with the Sinaloa Cartel to battle the Zetas.
He said the Mexican government deserves credit for taking down Coss and other high profile players in the Gulf Cartel.
"They’ve done a tremendous job, especially in the past month," Glaspy said.
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