By MATTHEW PENNINGTON, Associated Press
WASHINGTON (AP) — A U.S. research institute says satellite photos show signs of new tunnel work at North Korea's underground nuclear test site.
U.S.-Korea Institute at Johns Hopkins School of Advanced International Studies said Tuesday that it does not appear to indicate another underground blast is imminent at the Punggye-ri site.
But it suggests North Korea continues to work on its nuclear weapons program despite a recent easing of the tensions that followed its atomic test in February.
The commercial imagery shows gray spoil, apparently of rock from inside the mountain site, dumped near a tunnel entrance.
The work appears to have started by late April. The latest photo is from June 1.
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