North Korea conducts 3rd nuclear test; dares US

North Korea has successfully detonated a nuclear device in the northeastern province of Hamkyung, causing an explosion with a magnitude of 5.1, geological surveys in China and the US said.

The disturbance took place at a depth of about 1 kilometer in Kilju County, North Hamkyung Province, 378km (235mi) NE of Pyongyang.

"We can confirm that the test was conducted safely and perfectly at a high level, did not negatively affect the surrounding environment and was conducted with a higher-yield, smaller, lighter atomic device" North Korea's official state mouthpiece the KCNA said.

"The test was to defend our country's safety and sovereignty against the US's aggressive behaviour that infringed upon our republic's lawful right to peacefully launch a satellite"

...

Condemning the test, US President Barack Obama said: "This is a highly provocative act that, following its December 12 ballistic missile launch, undermines regional stability, violates North Korea's obligations under numerous United Nations Security Council resolutions, contravenes its commitments under the September 19, 2005 Joint Statement of the Six-Party Talks, and increases the risk of proliferation."

"North Korea's nuclear weapons and ballistic missile programmes constitute a threat to US national security and to international peace and security. The United States remains vigilant in the face of North Korean provocations and steadfast in our defence commitments to allies in the region."

"These provocations do not make North Korea more secure. Far from achieving its stated goal of becoming a strong and prosperous nation, North Korea has instead increasingly isolated and impoverished its people through its ill-advised pursuit of weapons of mass destruction and their means of delivery."

"The danger posed by North Korea's threatening activities warrants further swift and credible action by the international community. The United States will also continue to take steps necessary to defend ourselves and our allies. We will strengthen close coordination with allies and partners and work with our Six-Party partners, the United Nations Security Council, and other UN member states to pursue firm action."

The UN strongly condemned North Korea's underground nuclear test as "deplorable", saying it was a "clear and grave violation" of the Security Council resolutions and defied the unequivocal call from the world community to refrain from "provocative" measures.

"It is deplorable that Pyongyang defied the strong and unequivocal call from the international community to refrain from any further provocative measures," said a UN statement issued by the Spokesperson for Secretary-General Ban Ki-moon.

Ban urged North Korea to reverse course and work towards de-nuclearisation of the Korean peninsula, his spokesperson said.

Ban exuded confidence that the UN Security Council will remain united and take appropriate action.

The third nuclear test by North Korea, the first two conducted in 2006 and 2009, have shocked entire world.