Late 1970s: North Korea starts working on a version of the Soviet Scud-B, with a range of around 300km. 1980s-1990s:It carries out its first missile test in 1984, and begins developing longer-range missiles, including the Taepodong-1 (2,500km) and Taepodong-2 (6,700km), between 1987 and 1992. It tests the Taepodong-1 over Japan in 1998. 2006: First nuclear test. 2009: Second underground nuclear test. 2013: Third nuclear test. 2016: Pyongyang conducts two nuclear tests, the first of which is purportedly of a hydrogen bomb. It also test-fires a submarine-launched ballistic missile. On Aug 3, it fires, for the first time, a ballistic missile directly into Japanese-controlled waters. 2017: Tensions escalate.
•May: North Korea tests strategic ballistic rocket Hwasong-12, which has a mid-to-long range. It flies 700km before landing in the Sea of Japan, also known as the East Sea.
•July: On July 4, Pyongyang says it successfully tested an intercontinental ballistic missile capable of reaching Alaska, the Hwasong-14. The missile reaches an altitude of 2,802km and flies 933km during a flight of 39 minutes. A second test of the Hwasong-14 in late July sees it fly for 47 minutes to an altitude of 3,724km and a range of 998km. US President Donald Trump threatens Pyongyang with "fire and fury". The North says it is considering strikes near US strategic military installations in Guam.
•August: Ballistic missile fired over Japan.
•September: Sixth and largest nuclear test held on Sept 3. Monitoring groups say it was 16 times more powerful than the bomb that hit Hiroshima in 1945. On Sept 15, less than a week after the United Nations adopts an eighth series of sanctions, North Korea fires an intermediate-range missile over Japan, at a distance of 3,700km.
•November: Washington declares North Korea a state sponsor of terrorism. A week later, the North fires the Hwasong-15, which reaches an altitude of 4,475km and flies nearly 960km over 53 minutes. Based on its trajectory and distance, the missile would have a range of over 13,000km - more than enough to reach Washington and the rest of the US, says the Union of Concerned Scientists.
AGENCE FRANCE-PRESSE, REUTERS