The Mexican navy says it has rescued 10 migrants, including a baby, who were kidnapped by an armed gang in the northern state of Tamaulipas.
The navy said it found the captives by tracing a mobile phone call one of them made to a house in the city of Altamira.
Three policemen have been detained on suspicion of the kidnapping.
Mexico's criminal gangs often abduct illegal migrants heading north to the United States.
In August drug cartel gunmen massacred 72 mostly Central American migrants in Tamaulipas.
Most of the captives rescued in Altamira were migrants from Central and South America.
Four were from Colombia, two from El Salvador and one from Ecuador.
The three police officers arrived at the scene as navy troops were carrying out the rescue, and were detained after the captives identified them as their kidnappers.
Tamaulipas state is the scene of a bloody conflict between the rival Zetas and Gulf cartels, who are fighting for control of drug smuggling routes into the United States.
The Mexican navy has been playing a growing role in the fight against the drugs gangs, partly because local police forces have been infiltrated by the cartels.
Earlier this month navy marines killed the Gulf cartel leader Ezequiel Cardenas Guillen, known as "Tony Tormenta", in the city of Matamoros on the border with Texas.