N Korea’s H-bomb test a 'perfect success'

Pyongyang’s hydrogen bomb on Sunday resulted in tremors that shook buildings in China and Russia. HT takes a look at Pyongyang's journey to its latest nuke

1985

North Korea signs the Nuclear Non-Proliferation Treaty (NPT)

1993

North Korea threatens to pull out of NPT after the International Atomic Energy Agency (IAEA) calls for its inspectors to be given access to two nuclear waste storage sites

2002

US President George W Bush labels North Korea, Iran and Iraq an "axis of evil"

2003

North Korea withdraws from NPT, later declares it has nuclear weapons

2006

JULY: North Korea tests long range missiles

OCTOBER: North Korea claims to have successfully tested a nuclear weapon, resulting in UN Security Council sanctions

2007

North Korea agrees to close nuclear reactor in exchange for $400 million in aid

2009

North Korea conducts its second nuclear test, resulting in fresh UN Security Council sanctions

2012

FEBRUARY 29: US says North Korea has agreed to a moratorium on long-range missile launches and nuclear activity in exchange for aid MAY 24: South Korea claims the North appears ready to carry out a nuclear test "at any time"

2013

JANUARY 24: North Korea says will continue nuclear tests and long-range missile launches in defiance of the US, "the sworn enemy of the Korean people"

FEBRUARY 12: North Korea conducts third nuclear test

2015

MAY 20: North Korea claims it has the ability to miniaturise nuclear weapons, a key step toward building nuclear missiles DECEMBER 12: Pyongyang claims North Korea now has a hydrogen bomb in its arsenal

2016

JANUARY 6-7: North Korea claims to have successfully conducted a hydrogen bomb test

MARCH 9: North Korea says its miniature nuclear warheads can fit on ballistic missiles

SEPTEMBER 9: North Korea detonates a nuclear warhead, with an estimated explosive power of 10 kilotons

2017

JULY 4: North Korea claims it has conducted its first successful test of an ICBM that can "reach anywhere in the world"

AUGUST 9: North Korea says it is "examining the operational plan" to strike areas around the US territory of Guam

AUGUST 29: North Korea fires a missile that travels over Japan's Hokkaido island

SEPTEMBER 3: Pyongyang claims successful test of 'missile-ready' hydrogen bomb

AP South Korea’s Earthquake and Volcano Monitoring Division director Ryoo Yonggyu shows a chart of seismic waves caused by the hydrogen bomb, as measured on the Korean peninsula.

North Korean supreme leader Kim JongUn