New North Korean Nuclear Reactor Likely Running, U.N. Says

North Korea appears to be operating a more powerful reactor for producing plutonium at its main nuclear site for the first time, the United Nations atomic agency said late Thursday, days after Pyongyang tested an intercontinental ballistic missile that could reach across the U.S.

International Atomic Energy Agency Director General Rafael Grossi said that a light water reactor at North Korea’s Yongbyon nuclear facility was discharging warm water, indicating it was reaching criticality, the point at which its nuclear chain reaction becomes self-sustaining. The regime has been building the reactor for years.