Mexico City: Mexican President Andres Manuel Lopez Obrador said on Wednesday that a gang kidnapped a busload of around 50 migrants in the country's north.
Some of them have been rescued, and National Guard troops are searching the area around the northern Mexican city of Matehuala.
"They have already found some," the president added at a news briefing.
"Originally, there were reports of 50," he said. "We hope to rescue them."
What we know about the kidnapped migrants
Media reports said, citing officials, that nine people were rescued after they fled, meaning around 40 were still missing.
Officials said the migrants were traveling north toward the US in a bus from the southern state of Chiapas when they were attacked.
Those who were rescued were from Venezuela and Honduras, according to reports citing authorities in the northeastern state of Nuevo Leon.
The gang demanded a ransom of $1,500 (€1,383) for each kidnapped person, said the National Confederation of Mexican Transporters.
Latest incident in string of abductions
"Unfortunately, there are gangs that engage in kidnapping," Lopez Obrador said.
Gangs and drug cartels have long been active in the area where authorities are currently searching for the migrants.
In recent months, a string of such kidnappings has been reported, as gangs seem to increasingly charge migrants for fees to cross Mexico and then abduct them for ransom.
The National Institute of Migration has said that more than 2,100 migrants were kidnapped in Mexico last year.
Around 35 people, including tourists and migrants, were abducted last month in the country's northeast. They were later found in a desert area.