KYIV, UKRAINE (Association Press) – Ukraine’s nuclear power provider says Russian forces blindfolded and detained the head of Europe’s largest nuclear power plant hours after Moscow illegally annexed a swath of Ukrainian territory.

The alleged kidnapping comes at a pivotal moment in Russian President Vladimir Putin’s war. Facing a Ukrainian counteroffensive, Putin this week heightened threats of nuclear force and used his most aggressive, anti-Western rhetoric to date.

Ukrainian President Volodymyr Zelenskyy and his military vowed to keep fighting to liberate the annexed regions and other Russian-occupied areas.

Ukrainian officials said Saturday that their forces had surrounded thousands of Russian forces holding the strategic eastern city of Lyman, which is located in one of the four incorporated areas.