Today in Korean history

April 25

1960 -- A group of college professors issues a statement accusing the autocratic government of President Rhee Syng-man of using the police force to crack down on pro-democracy student protesters. Several hundred students were killed or injured in a clash on April 19, 1960, triggering nationwide anti-government protests. Rhee is later forced to step down and goes into self-imposed exile in Hawaii.

1965 -- South Korea establishes diplomatic relations with Bolivia.

1979 -- International phone service between South Korea and the Soviet Union is established.

1989 -- A Seoul court sentences self-confessed North Korean agent Kim Hyun-hee to death after she is convicted of bombing a Korean Air Lines jetliner near Myanmar, killing all 115 people on board. The death sentence was later commuted to life imprisonment. She was eventually freed in amnesty because the government said she was duped by the North's communist regime.

2007 -- North Korean leader Kim Jong-il inspects a massive military parade in Pyongyang marking the 75th anniversary of the founding of the country's armed forces.

2009 -- North Korea says it has restarted extracting plutonium from spent fuel rods in its major nuclear facility in an apparent response to a U.N. punishment for its April 5 rocket launch. The announcement by the North's foreign ministry comes just hours after the U.N. Security Council froze foreign assets of two firms and a bank in North Korea over their suspected ties to missile and nuclear programs.

2010 -- A team of military and civilian investigators says that a "non-contact external explosion," rather than a direct hit, was the most likely cause of the mysterious sinking of a South Korean warship on March 26.

Yoon Duk-yong, co-chairman of the joint investigation team, says the sinking of the Cheonan naval patrol ship near the western sea border with North Korea was most likely caused by a non-contact explosion under the warship, judging from initial inspections of the wreckage.

2014 -- Upholding a lower court ruling, a Seoul appeals court acquits a political defector of charges that he carried out espionage activities for Pyongyang. Yoo Woo-seong, the 34-year-old defector who formerly held Chinese nationality and lived in the North, was at the center of a high-profile forgery case in which Seoul's main intelligence agency was found to have fabricated Chinese government documents to frame him.

2019 -- North Korean leader Kim Jong-un holds his first summit with Russian President Vladimir Putin in Vladivostok, as Kim seeks to cement his ties with Moscow amid stalled nuclear negotiations with the U.S.

2022 -- North Korea holds a military parade in Pyongyang to mark the 90th founding anniversary of the Korean People's Revolutionary Army, the anti-Japanese guerilla force known to have been created by national founder Kim Il-sung in 1932.
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