CNN:
The United States and allies believe that North Korea is beginning to make preparations for a possible underground nuclear test for the first time since 2017.
North Korea has recently resumed digging tunnels and construction activities at its underground nuclear test site, according to five US officials. Commercially available satellite imagery had shown some indications of activity on the surface at Pyongyang’s remote Punggye-ri nuclear test site.
It is not yet clear how soon the regime would be capable of testing a device at the site, as it depends on the pace of the activity, the officials say.
The preparations for a possible underground nuclear test come after North Korea tested its first suspected intercontinental ballistic missile since 2017 earlier this month.
See also: U.S., S.Korea Seen Resuming Major Military Drills As N.Korea Tensions Rise