USGS is calling it an explosion.
http://earthquake.usgs.gov/earthquakes/eventpage/us10006n8a#executive
Earlier today a post at 38 North Blog said new activity has been detected at Punggye Ri
http://38north.org/2016/09/punggye090816/
Sent to Drudge.
A 5.3 on the Richter scale, a real nuke this time.
A poke in the eye to Obama.