A prominent clergyman has been arrested crossing back into his native South Korea from North Korea after an unauthorised visit.
Han Sang-ryol paid a two-month visit to communist North Korea, to which Seoul bans unauthorised trips.
The pro-reunification pastor was reportedly given a warm reception in the North.
But he faces criticism in the South, amid severely strained ties between the two Koreas.
'Tears of joy'
The BBC's John Sudworth, who is in Seoul, said Han Sang-ryol's homecoming was "highly unusual".
He crossed back into South Korea at the truce village of Panmunjom and was immediately taken away by authorities, witnesses said.
About 200 North Koreans reportedly gathered on the northern side of the border to bid farewell to the pastor, who arrived on 12 June.
About the same number of anti-reunification South Koreans were on the south side of the border village, along with about 1,000 riot police.
Mr Han was carrying a flag symbolising the reunification of the Korean peninsula; as conservatives in the South burned the same flag, another group of liberals were on hand to greet the pastor.
North Korean media said Mr Han met the number two leader, Kim Yong-nam, during his visit, and gave speeches denouncing South Korean President Lee Myung-bak.
It also quoted comments he made in support of reunification, saying he "will wait and wait for our reunion with tears of joy".
Our correspondent says that Mr Han's outspoken comments are a reminder that opinion in the South is often deeply divided over the best way to achieve reunification.
Despite the worsening relations between the two sides in recent years many still support the idea of closer ties and engagement with the old enemy.