North Korea has placed under house arrest for months a South Korean man who is believed to be the husband of a Japanese national abducted by North Korea in 1977.

The head of a South Korean association for abductees' families, Choi Sung-yong, said Friday that North Korean authorities have confined Kim Yong-nam and his family to their house outside of Pyongyang and strictly monitored their outside contacts.

Choi said he secured the information in a recent phone call from a North Korean in Shanghai who informed the group of Kim in 2004.