DPRK missile and nuclear timeline
December 1985
Pyongyang joins Treaty on the Non-Proliferation of Nuclear Weapons
February 1993
International Atomic Energy Agency demands to inspect suspected nuclear waste sites
June 1994
Withdraws from IAEA
August 1998
Launches three-stage rocket Taepodong 1 over Japan
January 2003
Withdraws from non-proliferation treaty
February 2005
Announces that country has produced nuclear weapons
July 2006
Test-fires ballistic missiles
Oct 9, 2006
Conducts first underground nuclear test
February 2007
Agrees to scrap nuclear facilities in return for aid
April 2009
Launches three-stage Unha 2 rocket
May 25, 2009
Conducts second underground nuclear test
November 2010
Reveals uranium enrichment facility to foreign experts
December 2012
Successfully launches Unha 3, including placement of satellite into orbit
Feb 12, 2013
Conducts third underground nuclear test
September 2015
Restarts Yongbyon reactor
Jan 6, 2016
Pyongyang says it has tested a hydrogen bomb
AFP - China Daily