Woo Yong-gak, 70, and 16 other men convicted of espionage were among 40 political prisoners freed Thursday under a special amnesty to celebrate the first anniversary of President Kim Dae-jung's inauguration.
"After living for decades in a closed place, I am so happy to walk out into this open world," Woo told reporters outside the fog-shrouded Taejon Penitentiary, 95 miles south of Seoul.
Woo said he hopes the government will allow him to return to North Korea, where he reportedly has a wife and son.
Outside the prison, about 30 activists shouted for the release of all political prisoners. Human rights groups say more than 200 such inmates remain in jail.
London-based Amnesty International and South Korean human rights groups say they believe Woo had been in jail longer than any other political prisoner in the world.
At a news conference Wednesday, Kim expressed willingness to swap the North Koreans for about 300 South Koreans captured during the 1950-53 Korean War and believed still held in the North. The North doesn't acknowledge the existence of South Korean POWs.
"I wish both sides would resolve the matter in a humanitarian way," Woo said.
Woo has been held in solitary confinement in a 12-by-12 foot cell since he was captured aboard a North Korean boat off South Korea's east coast in 1958.
He was seldom allowed outside his cell except for a daily 30-minute walk, human rights groups say. South Korean law specifies solitary confinement for spies, even if they pose no physical threat.
Woo said with a grin that he was in relatively good health, despite a stroke suffered several years ago.
"I thank South Korean human rights groups for helping me start a new life ... I also thank Amnesty International for bringing outside attention to our fate," he said.
About 1,490 other people also were freed from prison. The amnesty affected about 7,300 people who were convicted of minor crimes but have been out of prison on parole. They had their civil rights restored or their criminal records erased.
Since taking office, Kim has released 180 political prisoners who signed an oath to obey South Korean laws, including one making it a crime to espouse communism.
But the 17 convicted spies, all held for more than 29 years, had refused to sign the oath, saying it would violate their freedom of conscience and endanger their families in the communist North.
This time, the government decided not to demand an oath.
Some of the aging prisoners say they have never spied for the North but were caught, tortured and convicted in military courts in the 1960s after crossing the border to meet their relatives in the South.
The longest-serving political prisoner i South Korea now will be Sohn Sung-mo 71, a North Korean who has served 19 years after being arrested for spying, followed by Shin Kwang-soo, 71, a North Korean spy who has been in jail for the past 15 years.
Capitalist South Korea and the communist North remain technically at war because their 1950-53 conflict ended in a now-fraying truce rather than a peace agreement.
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