The sole survivor of a massacre that saw a Mexican drug cartel murder 72 people has told authorities his gruesome tale.
Luis Fredy Lala of Ecuador told authorities he was the only person to escape alive when gunmen massacred the 58 men and 14 women at a rural ranch just 100 miles from the U.S. border.
In an interview from his hospital bed, Lala said he was among a group of economic migrants from Central America abducted by armed men as they crossed into Mexico.
According to the Reforma newspaper, they were shot after refusing to pay ransoms.
The bodies of 72 people, believed to all be migrants, were found at a rural ranch in northern Mexico after the only survivor stumbled into a military checkpoint.
The victims were shot by the members of the Zetas cartel known for exploiting vulnerable people
The details of Fredy's tale were not published.
Marines from the Mexican Navy were sent to the building near San Fernando, in the troubled state of Tamaulipas where they fought a gun battle with fighters from the notorious Zetas cartel - made up of ex-special forces soldiers.
Three gunmen and one marine were killed in the fighting before soldiers made the grim discovery of the 72 bodies, some of them left lying in piles.
The victims are all believed to be immigrants targeted by one of the many competing drug cartels which have killed 28,000 people in Mexico in the last four years.
Increasingly, vulnerable migrants from countries such as Ecuador are being extorted by the gangs and even recruited into a life of drug trade-related violence.
'It's absolutely terrible and it demands the condemnation of all of our society,' said Mexican government security spokesman Alejandro Poire. Poire said the government was in contact with those countries to corroborate the identities of the migrants.
Consular officials from Brazil, Ecuador and El Salvador said they had no immediate information on whether any of their citizens were among the dead.
The marines seized 21 assault rifles, shotguns and rifles, and detained a minor, apparently part of the gang.
Authorities said they were trying to determine whether the victims had been killed at the same time as the reason for the killings remained unclear.
Poire said that migrants are frequently kidnapped by cartel gunmen demanding money, sometimes contacting relatives in the U.S. to demand ransoms.
He also said the government believes 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.
The 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 some 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.
Violence along the north-eastern 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.
Teresa Delagadillo, who works at the Casa San Juan Diego shelter in Matamoros just across from Brownsville, 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.
It was the third time this year that Mexican authorities have discovered large mass graves. In the other two cases, investigators believe the bodies were dumped at the sites over a long time.
The cartel has earned a brutal reputation in Mexico and across Central America and is controlled by former special forces soldiers
The Zetas control of the state of Tamaulipas is so brutal that many Mexicans do not dare to travel on its highways.
Many residents in the state tell of loved ones or friends who have disappeared travelling from one town to the next. Many of these kidnappings are never reported for fear that police are in league with the criminals.
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