North Korea conducted its fourth nuclear detonation on 6 January 2016 at 10:00:01 UTC+08:30. At the Punggye-ri Nuclear Test Site, approximately 50 kilometres northwest of Kilju City in Kilju County, an underground nuclear test was carried out. The United States Geological Survey reported a 5.1 magnitude earthquake from the location; the China Earthquake Networks Center reported the magnitude as 4.9.

The 2006 North Korean nuclear test was the detonation of a nuclear device conducted by North Korea on October 9, 2006.