(CNN) -- A group of 81 migrants held captive in a house in the border city of Reynosa were rescued by Mexican authorities.

A tip led state and federal agents to the two-story home where the migrants were held Wednesday. They had been held hostage there for several days, the Tamaulipas state public ministry said.

All but one of those rescued are Central Americans, the public ministry said. Men and women were among the captives, 39 from Honduras, 38 from Guatemala, three from El Salvador and one Mexican, the ministry said.

The migrants told authorities that they were attempting to enter the United States illegally.

The unidentified kidnappers escaped, the public ministry said.

Mass kidnappings of this sort are not unheard of. It is one of the many risks that Central American migrants face as they traverse Mexico.

In June, 52 migrants were rescued from another home in Reynosa. That same month, 165 migrants were rescued from the city of Gustavo Diaz Ordaez, also in Tamaulipas state.

Reynosa sits right on the U.S.-Mexico border, near McAllen, Texas.

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