Authorities in Taiwan are on the lookout for over 100 Vietnamese tourists that have been reported as missing after arriving in the country just before Christmas.

According to the National Immigration Agency, 152 of 153 Vietnamese nationals who arrived in four tour groups in Taiwan on December 21 and 23 were reported “missing” soon after, the Central News Agency reported.

One of the 152 was located and three others had left the country, but some 148 of the visitors were still missing.

As of 8am on Monday (January 7), some 47 of the 148 had been found, with 23 of them arrested and 24 surrendering to the police.

Media reports indicated that some of the Vietnamese said they paid around US$650 to join tour groups heading to Taiwan before opting to “go missing.” Others said that they left the tour groups in hope of being able to work illegally in Taiwan.

Authorities will continue to search for the remaining 70 men and 31 women.

Read: Vietnamese tourists become illegal immigrants in Taiwan