Kim Shin-jo, the only captured member of a team of 31 North Korean commandos who came within striking distance of the South Korean presidential palace ​in central Seoul before they were repelled in 1968, died on Wednesday. He was 82.

Mr. Kim’s death ​at a nursing hospital was confirmed on Thursday by his Sungrak Church in Seoul, which cited old age as the cause.

In January 1968, Mr. Kim and his colleagues did the unimaginable — slipping undetected through the heavily ​fortified border between North and South Korea and trekking 40 miles into Seoul on a mission to assassinate Park Chung-hee, who was the military​ dictator of South Korea at the time​, and his staff. They got within hundreds of yards of Mr. Park’s presidential Blue House but were stopped by South Korean forces​ in a fierce gun battle.

All the North Korean assassins were gunned down or killed themselves except two. One of the two was believed to have ​made it back to the North.​ The other was Mr. Kim​, ​who surrendered​ and later reinvented himself into a fiery anti-Communist lecturer and Christian pastor in the capitalist South.

“We came to slit President Park Chung-hee’s throat,” Mr. Kim said​ shortly after his capture.

The commandos’ raid into the heart of Seoul on Jan. 21, 1968 — and North Korea’s seizure of the American reconnaissance ship USS Pueblo two days later — marked one of the ​peaks of Cold War ​tensions on the divided Korean Peninsula.

Stung by the attack, Mr. Park’s government secretly trained its own assassins to exact revenge against ​the North’s then leader Kim Il-sung, the grandfather of the current leader Kim Jong-un. (The unit was disbanded after the South Korean commandos mutinied in 1971.) ​South Korea also ​created a reservist​ army and introduced military training at ​high schools and universities. The 13-digit residential ID card​, introduced ​at the time to ​help guard against North Korean spies, remains mandatory​ to this day for all South Koreans aged 17 or older.

Part of the mountain route behind the Blue House that ​Mr. Kim’s raiding party used ​to infiltrate the South Korean capital remained closed to the public​ for security reasons until a few years ago.

“If our mission had succeeded, South Koreans would be living under Communism now,” Mr. Kim said in an interview in 2008.

Korea was ​divided into the pro-Soviet North and pro-American South at the end of World War II. Their three-year Korean War ​was halted in a truce in 1953, leaving ​them technically at war ever since. ​In the ensuing decades, both sides​ waged a clandestine war, with thousands of commandos and spies infiltrat​ing each other’s territory​. Mr. Kim’s ​fallen comrades remain buried in an “enemy cemetery” north of Seoul, unclaimed by ​their government​, which officially denies both their mission and existence.

Back in 1968, Mr. Kim’s team breached a section of the western inter-Korean border guarded by ​American troops. As they were hurrying through the hills toward Seoul, the North Koreans encountered four South Korean brothers collecting firewood. After much debate, they let the South Koreans live, warning them not to contact the police. That was their fatal mistake.

The villagers alerted the police, and by the time the would-be assassins reached Seoul, the police were waiting.

A ferocious gun battle broke out around Bukaksan, a craggy hill behind the Blue House, which was the seat of the South Korean presidency until former President Yoon Suk Yeol relocated his office to another government building in 2022. The fighting and manhunt continued for two weeks as the North Korean raiding party scattered and retreated northward. ​More than 30 South Koreans were killed, too.

Mr. Kim was hiding in an abandoned hut, surrounded by South Korean troops and ready to kill himself with a grenade. He ​changed his mind and surrendered.

“I was single, a young man. I wanted to save myself,” he said in an interview in 2010.

North Korean spies caught in the South often spent decades in solitary confinement in South Korean prisons. Some of them refused to disown their Communist ideology, in part because doing so would jeopardize their families in the North. But after two years of interrogation, Mr. Kim was pardoned. He successfully argued that he didn’t kill any South Korean​s, and also disowned Communism.

South Korea saw propaganda value in converts like Mr. Kim. Soon after his release, he traveled across South Korea with counterintelligence officials, giving lectures at military ​units, churches and workplaces in which he railed against the North Korean government. He said that defectors from his North Korean hometown, Chongjin, told him that his parents were executed and his brothers had disappeared.

“In North Korea, my dead colleagues are heroes, and I am a traitor,” he said during the 2008 interview.

Mr. Kim was survived by his wife, Choi Jeong-hwa, whom he met in South Korea and who turned him to Christianity. Mr. Kim was ordained as a pastor in 1997.​ He was also survived by a son and a daughter.