REYNOSA, Mexico – Five South Koreans abducted in Mexico were set free unharmed on Tuesday, more than a week after they were kidnapped and held for ransom, officials said.

South Korea's Foreign Ministry announced the Koreans were in custody of Mexican police and would be handed over to the South Korean Embassy there.

In an interview with Radio Formula, Tamaulipas state attorney general Jose Herrera confirmed the five had been released Tuesday afternoon in Reynosa, and were meeting with embassy officials.

Mexican authorities said the South Koreans were kidnapped on July 14 while driving in Reynosa, across the border from McAllen, Texas, and their captors had demanded US$30,000.

Herrera said the four men and one woman were not in Mexico on business but instead were here looking to cross into the U.S. illegally.

“They were held so (their kidnappers) could profit for crossing them to the United States,” Herrera said.

He said investigators tracked several phone calls that led to the names of people-smugglers involved in the kidnapping. Herrera did not say if anyone had been arrested.

He said the released captives would be interviewed by federal investigators.

In Seoul, South Korea, Foreign Ministry official Lee Jeong-gwan told reporters the captors are believed to have released the Koreans after the Mexican authorities launched an effort to put strong pressure on them. Lee did not provide additional details such as whether ransom was paid to the kidnappers.

Thousands of South Koreans work in Mexico, many of them running import businesses or assembly-for-export factories.

Mexico has one of the highest rates of kidnappings for ransom in the world. Many abductions are never reported to police, in part for fear officials themselves might be involved or that they would bungle a possible rescue.

Associated Press Writer Hyung-jin Kim contributed to this report from Seoul, South Korea.