A Japanese man has recently been taken into custody in North Korea, government officials said Saturday as Tokyo tried to obtain information on the case.

According to informed sources, the man, in his 30s, was visiting the communist regime on a package tour organized by a foreign tourist agency. He was in Nampo, a port town in the western part of the country, the source said.

Japanese officials are concerned his detention could affect negotiations on the long-running abduction issue, which concerns Japanese who were kidnapped by North Korean agents in 1970s and 80s. Five were returned several years ago after talks held under the administration of Junichiro Koizumi.