A satellite mage of the Punggyeri Nuclear Test Site. Photo: Reuters

Recent commercial satellite images of North Korea’s Punggye-ri nuclear test site show that work on new tunnels is continuing — pointing to preparations for a future nuke test, according to an analysis by 38 North.

The respected Johns Hopkins University website dedicated to analyzing North Korea, says the digging is going on despite small tremors near Mt. Mantap — where the facility is located — in the wake of Pyongyang’s last nuclear test.

38 North analysts Frank V. Pabian, Joseph S. Bermudez Jr. and Jack Liu say the latest excavations continue to be concentrated at the West Portal, leaving the North Portal—where the last five tests were conducted—mostly dormant and likely abandoned, at least for the time being.

The analysts say there’s been a consistently high level of activity at the West Portal since the last nuclear test. Vehicles and personnel are said to be milling around the portal, with mining carts dumping fresh excavated material.

“These activities suggest that tunnel excavation is underway at the West Portal, as the North Koreans expand the site’s potential for future nuclear testing,” the analysts said.

Reports from Chinese and South Korean sources have previously said that small earthquakes, fatal cave-ins and nuclear contamination at Punggye-ri are interfering with the site’s use as a nuclear test facility.

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