South Korea urged North Korea on Wednesday to set free a South Korean Baptist missionary, in a repeated demand that follows Pyongyang's release of an American man.

Kim Jung-wook, 50, was arrested by the North's authorities in October last year while traveling there. He was sentenced by North Korea to hard labor for life on charges of spying and setting up underground churches.

"Our government once again calls on (North Korea) to free the missionary and repatriate him," unification ministry spokesman Lim Byeong-cheol said at a press briefing.

He was asked about Seoul's position on the issue of Kim as the North unexpectedly released Jeffrey Fowle, one of three Americans held there.

"Our government will make constant efforts, in cooperation with the international community, so that he will return to the arms of his family," added Lim.  

Meanwhile, the White House and the State Department announced the release of the 56-year-old Fowle, but the North's state-controlled media have kept mum on it.

The North is still detaining two other Americans: Kenneth Bae and Matthew Todd Miller. (Yonhap)