Mass kidnap of migrants reported in Mexico
El Salvador's foreign ministry said it condemned acts of aggression against migrants traveling through Mexico to the United States.
"The foreign ministry demands that the Mexican government investigate this," the ministry said in a statement.
But Mexico's interior ministry said it had found no evidence backing claims of the disappearance.
The nationality of those kidnapped was not immediately clear, although Solalinde said they included one woman from Honduras and three women from Nicaragua. Honduras has also asked Mexico for information about the case.
Some migrants pay as much as $10,000 to smugglers who promise to get them into the United States. Many others see their journeys end in robbery, assault or arrest. Women often report rapes during the voyage, and some have been forced into prostitution.
Corrupt Mexican police are often accused of playing a role, turning illegal migrants over to drug gangs for a price.
Countless Latin American migrants journey some 3,000 km (1,900 miles) through Mexico hoping for a better life in the United States, some clinging to the top of cargo trains or hiding in secret compartments built into tractor trailers.
(Reporting by Angelica Carcamo, Additional reporting by Gustavo Palencia in Tegucigalpa; Writing by Jason Lange and Krista Hughes in Mexico City; Editing by Philip Barbara and Eric Walsh)
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