North Korea has probably conducted a test of a nuclear explosive device this morning. The United Nations Security Council is expected to soon respond - possibly with new sanctions against Pyongyang.
According to seismic monitoring undertaken by the United States Geological Service and the Comprehensive Test Ban Treaty Organisation (CTBTO), a seismic event of 5.1 magnitude took place at 0130 GMT in the vicinity of North Korea's Pungyye-Ri Test Site.
DPRK state media has since claimed that the test was of a 'hydrogen bomb' - also known as a thermonuclear device - but this claim is yet to be substantiated. Expects have noted that the magnitude of the detected explosion suggests a smaller yield than would be expected of a true thermonuclear device.
Airborne and ground station monitoring for radionuclides should provide further clarity on the nature of the probable nuclear test.
The United Nations Security Council has reportedly set an emergency meeting in response to the event. If a new Security Council resolution is passed, further sanctions measures against North Korea can be expected.