Images show new work at NKorea's nuclear test site
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A US research institute says North Korea has made new tunnel entrances at its nuclear test site in a sign it is preparing to conduct more underground explosions there in the future. But the US-Korea Institute at Johns Hopkins School of Advanced International Studies says there's no sign that Pyongyang plans another test soon.
In February, North Korea conducted its third nuclear test since 2006, drawing tighter UN sanctions. It now says it is willing to resume aid-for-disarmament negotiations without preconditions. (AP)
