To demonstrate that North Korea is true to its determination to denuclearize, it blew up 3 tunnels at its Punggye-ri nuclear test site on May 24.
The demolition show is a part of Kim Jong Un’s grand deception. Research based on satellite images and seismic data shows these tunnels were partially or completely collapsed in the September 2017 nuclear test. They are of little or no value to North Korea. That no nuclear expert was allowed to inspect the site suggests the conclusions of the study were very likely correct.