Sequoyah nuclear power plant near Chattanooga, Tennessee. (Photo by Photorush via Flickr)

Siegfried Hecker, former director of the U.S. Los Alamos Nuclear Laboratory, and Jack Pritchard, a former U.S. envoy for negotiations with North Korea, confirmed construction activity in satellite images released by the institute as that consistent with a nuclear reactor.

Though it is not clear what North Korea plans on using the new reactor for, light-water reactors are generally used for civilian energy. But they can also be used to produce weapons grade plutonium.

f North Korea is building a reactor it would put the country in violation of United Nations resolutions, officials in Seoul say.

Last year, North Korea had been in talks with China, Japan, Russia, South Korea, and the U.S. about its nuclear programs, but stepped away from the bargaining table.

Read more about the reactor here.