Vietnamese authorities have detained a South Korean activist who helps North Korean refugees passing through the Southeast Asian nation, Seoul's foreign ministry said Monday.
The 51-year-old identified only by his surname Yoo was detained by intelligence officials at a hotel in Ho Chi Minh last Wednesday, a ministry spokesman told AFP.
Yonhap news agency, quoting South Korean embassy officials in Hanoi, said Yoo was held because of his work for the refugees but it was not immediately clear what exactly he was accused of.
The spokesman said Vietnamese authorities had not yet given the reasons for the arrest because the case was still under investigation. He said Seoul diplomats had asked to interview Yoo.
Tens of thousands of North Koreans, fleeing hunger or repression in their communist homeland, have fled in recent years. Virtually all cross the border to China, which repatriates those fugitives it catches.
Beijing says they are work-seekers rather than refugees, a policy criticised by international rights groups.
The North Koreans often travel on from China to Southeast Asian countries such as Thailand, Vietnam and Laos in hopes of flying from there to South Korea.