EL PASO, Texas (Border Report) – Authorities in Nuevo Leon have found nine of the 50 migrants abducted from a bus on Monday in the neighboring state of San Luis Potosi.

The migrants were in good health and told authorities they had been held in a safe house in Doctor Arroyo, a community near the border state of Tamaulipas, the San Luis Attorney General’s Office said in a statement.

The Heva Transportes charter bus picked up the migrants in the southern state of Chiapas and was stopped by members of the Gulf cartel on Federal Highway 57, which runs from Mexico City to Piedras Negras, according to Mexican news reports. The reports state the kidnappers demanded $1,500 for the release of each migrant, the driver and his assistant.

The bus company notified San Luis Potosi authorities it had lost track of the bus near the city of Matehuala, which falls under that state’s jurisdiction.

“We are engaged in collaborative patrols on the stretch near (Nuevo Leon) where the bus disappeared,” San Luis Attorney General Jose Luis Ruiz Contreras said in the statement.

Nuevo Leon police found the empty bus and the nine Venezuelan and Honduran nationals between the ages of 18 and 35 on Tuesday. There was no word on the whereabouts of the 41 remaining migrants nor the two drivers.

Jose Luis Lopez, vice president of the National Transportation Confederation, told Mexican media that Federal Highway 57 is among the most dangerous in Mexico due to the presence of organized criminal gangs.

“Many incidents are not being reported; other buses have been stopped and (passengers) robbed,” Lopez told Proceso, a Mexico City investigative news portal. “(It’s bad) that the government is not paying more attention to the security crisis. […] Things are getting complicated; there is no safety on the highways.”