Yonhap News Agency reporting recently cited ONN's Update: Developments at the DPRK's Punggye-Ri Nuclear Test Site between 24 March and 6 April 2022 and ONN senior analyst Katsuhisa Furukawa.
"Commercial satellite imagery taken between March 24 and April 6 indicates continued activity at the site's Tunnel 3, such as new spoil piles and a newly uncovered entrance, according to the report released by the Vienna-based Open Nuclear Network.
'The DPRK likely established a preliminary entrance to Tunnel 3 and started excavation of the tunnel structure,' read the report by Katsuhisa Furukawa, a former member of the U.N. Panel of Experts on North Korean sanctions. DPRK stands for the North's official name, the Democratic People's Republic of Korea."