The United States and North Korea have announced a nuclear-disarmament-for-aid deal after their first nuclear talks since the death of Kim Jong Il. Here's a timeline of some key developments of North-South tensions in Korean history:
_ Sept. 9, 1948: Kim Il Sung establishes the Democratic People's Republic of Korea in the northern half of the Korean peninsula.
_ June 25, 1950: North Korea invades the South, beginning the Korean War. United States backs South Korea, while China and the Soviet Union provide support to the North.
_ July 27, 1953: Korean War ends in armistice, not a peace treaty. Demilitarized Zone established along the border; U.S. military presence in South Korea remains.
_ January 1967: South Korean naval ship patrolling waters near maritime border sinks after being attacked by North Korean artillery. Thirty-nine of the 79 sailors on board are killed.
_ January 1968: Thirty-one North Korean commandos storm South Korea's presidential Blue House in failed assassination attempt against President Park Chung-hee. Seven South Koreans killed.
_ December 1969: North Korean spy hijacks and reroutes a South Korean airliner to North Korea. Thirty-nine hostages are freed after more than two months.
_ November 1987: Bombing of Bangkok-bound South Korean airliner kills 115 passengers and crew. Two North Korean spies are found responsible.
_ July 8, 1994: Kim Il Sung dies of a heart attack at age 82. His son, Kim Jong Il, succeeds him as leader.
_ Mid-1990s: North Korea suffers a devastating famine that kills an estimated 5 to 10 percent of its population.
_ Spring 2009: North Korea withdraws from talks with its neighbors and the U.S. over ending its nuclear program and conducts a second nuclear test.
_ March 26, 2010: Explosion sinks South Korean naval ship near Koreas' western maritime border, killing 46 sailors. An international investigation later finds North Korea to be responsible for the sinking.
_ September 2010: Kim Jong Il unveils his third son, the twenty-something Kim Jong Un, as his successor, and assigns him to high-ranking positions in the Workers' Party and military.
_ Nov. 23, 2010: North Korea fires dozens of rounds of artillery onto a populated South Korean island near their disputed western sea boundary, killing four people. South Korea returns fire and scrambles fighter jets.
_ July 22, 2011: During the Southeast Asian regional security conference in Bali, Indonesia, top nuclear envoys from North and South Korea emerge smiling from their first meeting since 2008, say they are ready to work together to resume stalled disarmament talks.
_ July 27, 2011: Senior North Korean diplomat visits New York to negotiate ways to restart six-nation nuclear disarmament talks.
_ Oct. 24, 2011: U.S. and North Korean diplomats open talks in Geneva on Pyongyang's nuclear program.
_ Nov. 30, 2011: North Korea says it is making rapid progress on work to enrich uranium and build a light-water nuclear power plant, increasing worries that the country is developing another way to make atomic weapons.
_ Dec. 19, 2011: North Korea announces that Kim Jong Il has died of a heart attack while riding on his personal train. South Korea puts its military on alert while people break into tears on the streets of Pyongyang as they learn the news. Kim Jong Un dubbed "great successor."
_ Dec. 30, 2011: North Korea warns the world there will be no softening on its position toward South Korea's government.
_ Feb. 23, 2012: Amid cautious optimism, U.S. and North Korean envoys meet in Beijing for their first talks on dismantling Pyongyang's nuclear programs since the death of Kim Jong Il.
_ Feb. 29, 2012: In concurrent announcements, the U.S. and North Korea say they have reached a deal for the U.S. to provide food aid to North Korea in exchange for the North's suspension of uranium enrichment and a moratorium on nuclear and long-range missile tests.