Mexican President Felipe Calderon has condemned the massacre of 72 suspected migrants from Central and South America, blaming drug cartels for the killings.
In a statement late Wednesday, President Calderon said the drug gangs are carrying out more extortions and kidnappings of migrants as their resources and recruits dwindle.
The president says government crackdowns on the cartels have significantly weakened them.
Mexican officials are consulting with authorities from several other Latin American countries for help in identifying the bodies of 58 men and 14 women discovered at a farm in northern Mexico Tuesday. They say the migrants are believed to have been from El Salvador, Honduras, Brazil and Ecuador.
An Ecuadorean man, claiming to be the only survivor of the massacre, said the migrants were kidnapped by an armed group and taken to the ranch, near the town of San Fernando, about 100 kilometers south of the border with the U.S. state of Texas.
He told investigators the captors identified themselves as members of the Zetas drug cartel.
Officials say troops went to investigate after the Ecuadorean approached a checkpoint and said he had been attacked at the ranch.
The troops discovered the bodies following a shootout with suspected cartel gunmen. One soldier and three of the suspects were killed.
Mexico's drug cartels are locked in a violent battle for control of trafficking routes into the United States.
President Calderon launched a crackdown on the cartels in 2006. More than 28,000 people have been killed in the country's drug war since he took office.
Some information for this report was provided by AP, AFP and Reuters.