From Drudge Quake Sheet:
5.3
Explosion 15km ENE of Sungjibaegam, North Korea
2016-09-09 00:30:01 (UTC)
0.0 km
The Drudge Quake sheet is always posted on Drudge.
This website says 5.3 Richter equates to 90 kilotons of exploding TNT.
http://www.english.ucla.edu/all-faculty/335-kelly-kiloton-index-of-earthquake-moment-magnitudes