North Korea may be restarting nuke plant, according to images reviewed by US institute

This Jan. 2, 2015, image provided by Airbus Defense and Space, Spot Image, and Pleiades - CNES via 38 North, a website specializing in analysis of North Korea, at the U.S.-Korea Institute at the Johns Hopkins School of Advanced International Studies shows an annotated satellite photo indicating signs of new activity at the 5 MWe Plutonium Production Reactor at North Korea’s Nyongbyon Nuclear Scientific Research Center. The U.S.-Korea Institute at Johns Hopkins School of Advanced International Studies said on Thursday, Jan. 29, 2015, that North Korea may be attempting to restart its main nuclear bomb fuel reactor after a five-month shutdown. (AP Photo/Airbus Defense and Space, Spot Image, Pleiades - CNES via 38 North) (The Associated Press)

SEOUL, South Korea – A U.S. research institute says North Korea may be attempting to restart its main nuclear bomb fuel reactor after a five-month shutdown.

If true, the finding Thursday, will be an added worry for the United States and the North's neighbors at a time of increasing animosity.

The Nyongbyon reactor restarted in 2013 after being shuttered under a 2007 disarmament agreement. It has been offline since August.

Possible signs in satellite imagery from Dec. 24 through Jan. 11 that the reactor is being restarted include hot water drainage from a pipe at a turbine building and growing snow-melt on the roofs of the reactor and turbine buildings.

The U.S.-Korea Institute at Johns Hopkins School of Advanced International Studies says more monitoring is needed to reach a definitive conclusion about what's happening.