North Korea appears to have made a major upgrade to its main nuclear facility that could double the country's capacity to produce weapons-grade uranium, a defense analytics firm said Tuesday.
The secretive state appears to have put into operation a second centrifuge hall at its Yongbyon site, around 50 miles north of Pyongyang, according to analysis of new satellite images by IHS Jane's.
Centrifuges are an essential part of enriching uranium used for nuclear energy plants and atomic bombs. North Korea is believed to have around 10 nuclear warheads but not the missile technology to deliver them.
"Lots of people are very concerned about North Korea's nuclear program," IHS Jane's analyst Karl Dewey said. The apparent new centrifuge hall "could potentially double North Korea's ability to produce weapons-grade uranium," he told NBC News.
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Dewey added such a development in the country's nuclear infrastructure "further entrenches North Korea's behavior" and would make "roll-back harder" were the country ever to engage with Western nations in non-proliferation talks.
The satellite images taken in January and February showed melted snow around the building which indicated heat coming from inside. The building also has similarities to an existing centrifuge hall that North Korea says is for energy production.