North Korea on Saturday freed four South Korean fishermen held since July after their boat strayed into waters governed by the secretive state.
The gesture comes amid thawing relations on the Korean peninsula and a joint announcement Friday that the two countries would resume a series of reunions between families that have been divided for decades since the Korean War.
North Korean officials handed over the men and their boat at the eastern sea border between the two countries, officials said.
"I am very pleased, and it's beyond expression," Lee Ah-na, the wife of the boat's captain, told the Associated Press from the eastern port of Geojin, just south of the border.
Negotiations to resume the family reunions after a two-year hiatus led to an agreement to hold six days of temporary reunions with 200 families beginning Sept. 26, according to a joint statement.
Both sides said they would seek families that have not had any mail, phone or e-mail contact in the last 56 years.
One North Korea expert said Saturday that Pyongyang's gestures signal a new policy toward the outside world.
"North Korea sees relations with South Korea in parallel with those with the United States," said Paik Hak-soon, director of the Center for North Korean Studies at the Sejong Institute near Seoul. "So, with South Korea, North Korea seeks to achieve a framework for peaceful co-prosperity."
Tensions peaked earlier this year after Pyongyang conducted a series of missile tests followed by an underground nuclear explosion, setting off a flurry of condemnation by the U.S., Japan and South Korea.
But matters have improved since former President Clinton arrived in Pyongyang this month to secure the release of two American journalists who had been held by North Korea.
Conservative South Korean President Lee Myung-bak last week met briefly with several Pyongyang officials who had traveled south to pay respects to Kim Dae-jung, the former South Korean president who died after a bout of pneumonia.
Four North Korean officials also visited Los Angeles this month to meet with American relief organizations to discuss the resumption of food aid, but did not meet with U.S. government officials, according to Yonhap news service in Seoul, citing unidentified sources in Washington.
Ju-min Park of The Times' Seoul Bureau contributed to this report.