(Bloomberg) -- Satellite images indicate North Korea may be close to completing a new reactor in its major nuclear complex in Yongbyon, according to 38 North, a Washington-based website that tracks events in the country. 

Construction crews are working on a support building at the site’s Experimental Light Water Reactor (ELWR) development and water discharges have been spotted near the ELWR’s pump house that could be associated with testing of the reactor’s cooling system, the website said. 

North Korean leader Kim Jong Un visited a facility producing nuclear bombs earlier this week and reiterated his order to massively expand the North’s nuclear arsenal. Kim said North Korea is ready to use nuclear weapons “anytime and anywhere,” the official Korean Central News Agency reported. His visit to the facility came as the nation carried out series of weapon tests including ballistic missiles designed to deliver a nuclear warhead. 

The Yongbyon site’s existing 5 MWe reactor has been running since July 2021 and commercial satellite images from March show there’s new construction for the reactor’s spent fuel storage building, according to 38 North. 

“Together, these developments seem to reflect Kim Jong Un’s recent directive to increase the country’s fissile material production to expand its nuclear weapons arsenal,” the website said. 

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