North Korea claimed on Sunday that it had launched a long-range rocket and successfully placed an Earth observation satellite into orbit, but the US and its allies suspect the move was a cover to test a ballistic missile capable of carrying a nuclear warhead.
The following are Pyongyang's key missile and atomic tests:
August 31, 1998: North Korea launches an intermediate-range Taepodong-1 missile, but it fails to put a satellite into orbit.
July 4, 2006: North Korea test-fires the more advanced Taepodong-2 missile, but the test fails.
October 9: North Korea carries out its first atomic test.
October 14: The UN Security Council unanimously imposes commercial sanctions and bans North Korea from importing ballistic missile technology in response to its nuclear test.
April 5, 2009: North Korea launches a Unha-2 rocket and says it placed a satellite into orbit, but outside experts said no satellite is detected.
May 25: North Korea conducts its second atomic test.
June 12: The UN Security Council unanimously adopts stricter sanctions, including the interception of North Korean ships.
April 13, 2012: North Korea launches a long-range Unha-3 rocket, which explodes minutes after takeoff.
December 12: North Korea says a launch of another Unha-3 rocket was successful and it placed a satellite into orbit.
January 22, 2013: The UN Security Council condemns the latest launch and extends asset freezes and travel bans to several North Korean organizations and individuals.
February 12: North Korea appears to carry out its third atomic test, according to seismic data. Pyongyang claims it used a miniaturized nuclear device, but no radiation was detected.
November 28: Increased activity at the North's Yongbyon facility prompts international observers to suspect the regime is restarting production of fissile material.
March 26, 2014: North Korea launches two ballistic missiles that fly about 650 kilometres and reach Mach 7 before falling into the sea east of the peninsula.
October 8: North Korea's nuclear test site at Punggye-ri ceases activity, intelligence agencies say, prompting speculation of an imminent fourth nuclear test explosion but none was reported.
September 15, 2015: North Korea says it has restarted operations of the nuclear reactor at its Yongbyon facility after making "innovations" at the complex.
January 6, 2016: North Korea claims it has successfully tested a hydrogen bomb, its fourth test of an atomic device, but Western experts doubted it was such a powerful device.
February 7: North Korea launches a long-range rocket and says it has successfully put Earth observation satellite Kwangmyongsong-4 into orbit.