On September 3 , at 3:31 am UTC , the United States Geological Survey reported that it had detected a magnitude 6.3 earthquake in North Korea near the Punggye-ri test site . Given the shallow depth of the quake and its proximity to North Korea 's primary nuclear weapons testing facility , experts concluded that the country had conducted a sixth nuclear weapon test since the country first exploded a nuclear device in 2006 . North Korea claimed that they had tested a hydrogen bomb capable of being mounted on an ICBM . The independent seismic monitoring agency NORSAR estimated that the blast had a yield of around 120 kilotons . An official KCNA statement of September 3 , also claimed North Korea 's ability to conduct a " super-powerful EMP attack "
sixth nuclear weapon test
2017 North Korean nuclear test
2017–18 North Korea crisis