North Korea expands its uranium enrichment facility

North Korea has built a new two-storey uranium enrichment facility at its main Yongbyon nuclear complex, the International Atomic Energy ‌Agency (IAEA) said, calling it a cause for "serious concern". It's reportedly capable of housing up to 28 centrifuge cascades used to enrich uranium. Moreover, it has also begun operating an expanded annex at another enrichment site.