The Coup d'état of December Twelfth or the "12/12 Incident" was a military coup d'état taken place on December 12, 1979 in South Korea.

Chun Doo-hwan ordered the arrest of Army Chief of Staff General Jeong Seung-hwa without authorization from then-President Choi Kyuha, alleging involvement in the assassination of the ex-President Park Chung-hee. This led to a bloody shoot-out at the Army Headquarters and the Ministry of Defense. By the next morning, Chun and his fellow eleventh class military academy graduates Roh Tae-woo and Jeong Ho-yong were in charge of the Korean military.

See also

• Gwangju Massacre