Lucian Kim

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On the day Olga Skripnik fled her home in Crimea, many of her fellow Crimeans were celebrating.

On March 16, 2014, separatist leaders in the Ukrainian province rushed through a referendum on joining Russia in violation of Ukraine's constitution. The controversial measure, which few countries recognized, passed overwhelmingly under the watchful eyes of a Russian occupation force that had seized the Crimean Peninsula two weeks earlier.

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When heavily armed Russian troops began fanning out across Crimea in February 2014, one man stepped out of the shadows to lead the movement to break off from Ukraine and join Russia.

Sergei Aksyonov, then the head of a small pro-Kremlin party, was appointed the leader of Crimea and oversaw a referendum in favor of the split that few countries recognized. The lightning Russian takeover was a watershed moment, leading to a downward spiral in relations between Moscow and the West.

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More than two months after a mysterious radioactive cloud was detected over Europe, Russia's nuclear industry went public Friday in an attempt to dispel fears that one of its facilities had released a plume of ruthenium-106.

Russia's state nuclear corporation, ROSATOM, released the findings of a special commission, which concluded that the Mayak nuclear reprocessing plant, near the border with Kazakhstan, could not have been the source of ruthenium-106, a radioactive isotope.

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President Trump had a long phone call with Vladimir Putin yesterday, and they talked mostly about some of the world's most complicated global security issues. Here's the president as he was boarding his helicopter yesterday.

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