A US research institute says North Korea may have temporarily shut down a plutonium reactor earlier this year as it grappled with water supply problems that could threaten the safety of its nuclear complex.
The North restarted the reactor at the Nyongbyon complex only last summer, backtracking on a commitment of previous aid-for-disarmament negotiations.
A constant water supply from a nearby river is essential to cool the reactor and another reactor under construction. US-Korea Institute says satellite imagery show the recently restarted reactor may have been temporarily shut down or operated at a lower power level for repairs after flooding caused the river to change course.
The reactor appears to have been operating again by mid-February.
The findings are being published yesterday on the institute's web site, 38 North.
