U.S. Spy Ship Captured by North Korea Almost Caused Nuclear War and Is Still There 50 Years Later

A North Korean navy seaman stands aboard the USS Pueblo, an armed Navy intelligence-gathering ship captured by North Korean forces in 1968, in Pyongyang on July 27, 2013. North Korea celebrated the 50th anniversary of the vessel's seizure. GILES HEWITT/AFP/Getty Images

A U.S. spy ship captured by North Korea exactly 50 years ago today still floats, located now in a war museum in the capital Pyongyang, where its celebrated as a victory over Washington's plans abroad.

The official Korean Central News Agency published an article Tuesday praising the seizure of "imperialist armed spy ship" USS Pueblo on January 23, 1968, the dawn of the Vietnam War and just after North Korean agents attempted to assassinate the president of South Korea at his residence.

Both Washington and Pyongyang have blamed one another for the incident, but North Korea considered its refusal to return the ship a milestone at a particularly tense point in a long history of defying U.S. military pressure.

Related: North Korea Reveals How It Defied U.S. and Other Nations Failed

"At that time, the U.S. drove the situation of the Korean Peninsula to the brink of war by dispatching its nuclear aircraft carrier Enterprise and mobile strike forces to the East Sea of Korea while threatening to use nuclear weapons unless the DPRK would send back the spy ship," the agency wrote, referring to an acronym for the country's official title—the Democratic People's Republic of Korea.

"However, the DPRK declared its stand that it would react to the U.S. 'retaliation' with retaliation and to an all-out war with an all-out war. The DPRK's toughest stance forced the U.S. to sign a letter of apology that the government gives [a] firm assurance that no U.S. ship will intrude into the territorial waters of the DPRK again in the future," it added.

A North Korean navy seaman stands aboard the USS Pueblo, an armed Navy intelligence gathering ship captured by North Korean forces in 1968, in Pyongyang on July 27, 2013. North Korea celebrated the 50th anniversary of the vessel's seizure January 23, 2018. GILES HEWITT/AFP/Getty Images

The USS Pueblo was officially designated as a Banner-class environmental research ship, a term used to describe vessels gathering intelligence on foreign foes at the height of the Cold War in the 1960s. The ship was dispatched on January 11, 1968, by U.S. forces in Japan to spy on Soviet and North Korea naval assets in the Pacific, as well as to "determine Soviet and North Korean reaction to an overt intelligence collector operating near periphery and conducting surveillance of naval units," according to a declassified National Security Agency report on the incident.

On January 20, 1968, the USS Pueblo encountered a North Korean submarine chaser passing nearby and two North Korean fishing trawlers on January 22. On January 23, the submarine chaser returned demanding the spy ship to leave or be fired upon. North Korean reinforcements arrived and ultimately attacked the U.S. vessel, wounding several sailors, one of whom later died from his injuries.

The 82 surviving crew members were taken to prisoner of war camps where they claimed to have been tortured, especially after guards discovered the U.S. prisoners had been giving them the middle finger in propaganda photos, according to an account given by commanding officer Lloyd Bucher to newsweekly Human Events in 2001. After being forced to confess, Lloyd said he did manage to sneak in a pun by mispronouncing "paean" (meaning "to sing the praise of") in stating his "fervent desire to pee on the Korean People's Army Navy, and their government"

The detained U.S. sailors became the subject of heated negotiations between the U.S. and North Korea, which demanded an official apology over the incident and an admission that the U.S. had been spying. During the 11-month crisis, U.S. military leadership came up with a plan to assault North Korea with a coordinated nuclear attack, known as Operation Freedom Drop, the same year. The U.S. eventually did apologize for spying, although it later retracted the statement after the men were released just two days before Christmas.

North Korean army guide Kim Mi Gyong shows the letter of apology on the USS Pueblo, a 176.5-feet-long ship North Korea seized in 1968 after accusing its crew of spying in its territorial waters, 28 March 2005. The incident, which almost brought the two nations to war, ended after 11 months in captivity for the crew and an apology for the North Koreans. PETER PARKS/AFP/Getty Images

A declassified, in-depth 1992 National Security Agency report said the incident lived on in U.S. military psyche because of the realization that a Navy ship "had been fired upon and seized on the high seas for the first time in 160 years." U.S.'s failure to defend or even recover the ship were also listed as reasons the event was described as "distasteful."

Half a century after the attack, the Korean Central News Agency said "millions" visited the ship at its current location beside the Victorious Fatherland Liberation War Museum, a site dedicated to the three-year war fought between Soviet- and Chinese-backed North Korea and its southern rival, which was supported by the U.S. and United Nations forces in the early 1950s.

That conflict, like the USS Pueblo incident, have been used by all three generations of North Korea's ruling Kim family as potent reminders of U.S. aggression and justification for the authoritarian state's development of a nuclear deterrent, which included weapons of mass destructions and missiles capable of delivering them around the world.