South Korea's Foreign Ministry says kidnappers have released five South Korean hostages in northern Mexico.

A ministry official in Seoul said the four men and one woman were released unharmed early this morning Korean time.  The official, Lee Jeong-gwan, said they will be handed over soon to South Korean authorities.

The kidnap victims were seized on July 14 while they traveled by car in the city of Reynosa, along Mexico's border with the United States.  They were in Mexico seeking jobs.

South Korea's Yonhap newspaper reported that the kidnappers called the families of the victims seeking $30,000 in ransom.

The U.S. State Department said in a recent travel alert that foreign visitors and residents have been among the victims of kidnappings and homicides in Mexico's border region. 

The alert warned that no one can be considered immune from kidnapping on the basis of occupation, nationality or other factors and that many of these abductions are for ransom.

The government of Mexican President Felipe Calderon has deployed troops in various parts of the country to crack down on violence.

Some information for this report was provided by AFP, AP and Reuters.