I've come across a few blog posts today that claim to tell us the locations of the nuclear tests carried out recently by North Korea. This location posted by willyritch reveals a group of buildings in a mountain range, while this location linked by Ryan Schultz cites the USGS Seismic Activity Report as it's reference.
DIY nuke monitoring: North Korea (OgleEarth)
North Korean Nuclear Test in Google Earth (Google Earth Blog)
Related: Google Nuclear Maps