Mexican security forces were bringing refrigeration equipment for the bodies of 72 Central and South American migrants massacred by drug cartel gunmen at a remote ranch in northern Mexico, while investigators tried Thursday to determine their identities and why they were gunned down 100 miles (160 kilometers) from the U.S. border.
The sole survivor — an Ecuadorean who escaped and stumbled wounded to a marine checkpoint on a highway — told authorities that his captors had identified themselves as Zetas, a drug gang whose control of parts of the northern state of Tamaulipas is so brutal and complete that even many Mexicans avoid traveling its highways.
If confirmed as a cartel kidnapping, the Tamaulipas massacre would perhaps be the most extreme case seen so far and the bloodiest massacre of Mexico's drug war.
President Felipe Calderon said cartels are increasingly trying to recruit migrants as foot soldiers — a concern that has also been expressed by U.S. politicians demanding more security at the border.
He insisted that such activities indicated the cartels have been battered by thousands of troops and federal police battling them in their strongholds, and are desperate for alternate means of income.
Calderon frequently makes that argument, while critics counter that Mexico's cartels have only gotten more powerful and brutal since the government launched its offensive against the cartels in late 2006.
The drug gangs "are resorting to extortion and kidnappings of migrants for their financing and also for recruitment because they are having a hard time obtaining resources and people," Calderon said in a statement Wednesday night.
Authorities said they were trying to determine whether the 72 victims in Tamaulipas were killed at the same time — and why. The government was taking the bodies from the ranch to the small town of San Fernando for identification, and will have to move in refrigeration equipment that the local authorities lack, said Ricardo Najera, a spokesman for the federal Attorney General's Office.
Investigators believe the migrants were from Ecuador, Brazil, El Salvador and Honduras.
A spokesman for Brazil's foreign ministry said the vice consul of the Brazilian Embassy in Mexico City will be among several diplomats flown by the Mexican government to San Fernando to "help in any way he can with the investigation." He asked not to be identified because he is not authorized to discuss the matter with the news media.
Marcio Araujo, Brazil's consul general in Mexico, said documents found at the scene indicated at least four of the dead were Brazilian.
Migrants running the gauntlet up Mexico to reach the United States have long faced extortion, violence and theft. But reports have grown of mass kidnappings of migrants, who are forced to give the telephone numbers of relatives in the United States or back home who are then required to transfer ransom payments to the abductors.
Teresa Delagadillo, who works at the Casa San Juan Diego shelter in Matamoros just across from Brownsville, Texas, said she often hears stories about criminal gangs kidnapping and beating migrants to demand money — but never a horror story on the scale of this week's massacre.
"There hadn't been reports that they had killed them," she said.
In an April report, Amnesty International called the plight of tens of thousands of mainly Central American migrants crossing Mexico for the U.S. a major human rights crisis. The report called their journey "one of the most dangerous in the world" and said every year an untold number of migrants disappear without a trace.
Mexico's government has confirmed at least seven cases of cartels kidnapping groups of migrants so far this year, said Antonio Diaz, an official with the National Migration Institute, a think tank that studies immigration.
But other groups say migrant kidnappings are much more rampant. In its most recent study, the National Human Rights Commission said 1,600 migrants are kidnapped in Mexico each month. It based its figures on the number of reports it received between September 2008 and February 2009.
On Tuesday, Ecuadorean migrant Luis Freddy Lala Pomavilla staggered to the checkpoint with a bullet wound in his neck. He told the Mexican marines he had just escaped from gunmen at a ranch in San Fernando, 100 miles (160 kilometers) south of Brownsville, Texas.
The marines scrambled helicopters to raid the ranch, drawing gunfire from cartel gunmen. One marine and three gunmen died in the gunbattle.
Then the marines discovered a hellish scene: piles of people, some of them blindfolded and with their hands tied behind their back, slumped on top of each other along the cinderblock walls at the ranch.
The 58 men and 14 women were killed by the Zetas gang, the migrant told investigators Wednesday. The gang, started by former Mexican army special forces soldiers, is known to extort money from migrants who pass through its territory.
The marines seized 21 assault rifles, shotguns and rifles, and detained a minor, apparently part of the gang.
Violence along the northeastern border with the U.S. has soared this year since the Zetas broke with their former employer, the Gulf cartel. Authorities say the Gulf cartel has joined forces with its once-bitter enemies, the Sinaloa and La Familia gangs, to destroy the Zetas, who have grown so powerful they now have reach into Central America.
It was the third time this year that Mexican authorities have discovered large masses of corpses. In the other two cases, investigators believe the bodies were dumped at the sites over a long time.
The Rev. Alejandro Solalinde, who runs a shelter in the southern state of Oaxaca, where many migrants pass on their way to Tamaulipas, said the Zetas have put informants inside shelters to find out which migrants have relatives in the U.S. — the most lucrative targets for kidnap-extortion schemes.
He said he constantly hears horror stories, including people who "say their companions have been killed with baseball bats in front of the others."
Solalinde said he has been threatened by Zetas demanding access to his shelters.
He said the gangsters told him: "If we kill you, they'll close the shelter and we'll have to look all over for the migrants."
Associated Press Writers Alicia A. Caldwell in El Paso, Texas, and David Koop in Mexico City, contributed to this report.