WASHINGTON (AP) - A U.S. institute says satellite images show North Korea is digging a tunnel at its nuclear test site but another underground explosion is unlikely in the next few months.
The recent execution of ruler Kim Jong Un's powerful uncle has heightened concern about the stability of the North Korean regime and that it may resort to an attention-grabbing provocation, like a nuclear test.
The website of the U.S.-Korea Institute said Friday that imagery of the Punggye-ri site indicates excavation of a probable new tunnel at a portal used for a February explosion, but it's likely some way from completion.
The website, 38 North, estimates the volume of earth excavated since May and piled nearby suggests some 500 meters of tunnel has been dug since then, meaning it could be half-complete.
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