The Ukrainian military on May 30 denied Russia's claim that a Ukrainian drone struck a power unit at the Zaporizhzhia Nuclear Power Plant (ZNPP). "The Ukrainian Defense Forces did not strike power unit No. 6 of the Zaporizhzhia Nuclear Power Plant," the Southern Defense Forces said in a statement denying Russia's allegation."Ukrainian servicemen act exclusively within the norms of international humanitarian law and are aware of the consequences of any actions on nuclear facilities."Earlier in the day, Alexey Likhachev, head of the Russian state nuclear corporation Rosatom, alleged that a Ukrainian fiber-optic drone struck the machine room of the nuclear plant's reactor No. 6. Likhachev claimed that a hole appeared in the wall of the building, though no equipment was damaged. He also alleged that the attack was deliberate, as the drone was controlled by a fiber-optic cable. The Rosatom chief alleged that the strike marked Ukraine's first targeted attack on the main equipment of the Zaporizhzhia Nuclear Power Plant, which has been occupied by Russian forces since March 2022. Russia provided no evidence to support its allegations.The Ukrainian military refuted the allegations altogether, accusing Russia of disinformation and nuclear blackmail. "The Russian Federation continues to use the Zaporizhzhia Nuclear Power Plant as an instrument of nuclear blackmail and information provocations," the Southern Defense Forces said. "The reports spread by occupation resources about the alleged strike by the Ukrainian Defense Forces on the facilities of the Zaporizhzhia Nuclear Power Plant are another attempt to discredit Ukraine and hide their own criminal actions."The military pointed out Russia's failure to provide photo or video evidence backing up its claims, and said that Ukraine does not possess fiber-optic drones with sufficient range to strike the ZNPP. "The version promoted by Russia does not withstand any verification of the facts," the military said. The Zaporizhzhia Nuclear Power Plant is Europe's largest nuclear power plant and among the 10 largest in the world. Ukraine has repeatedly warned that Russia's occupation of the plant poses one of the greatest threats to nuclear safety — not just in Ukraine, but worldwide.The United Nations' nuclear watchdog, the International Atomic Energy Agency (IAEA), warned in May 2026 that increased drone activity near the ZNPP intensified the risk of a nuclear accident at the site. The plant lost both landline and internet connections for about 12 hours on May 27, marking the longest such outage at the facility since the start of Russia's full-scale invasion of Ukraine, according to the IAEA.The communications outage violated one of the seven core principles for maintaining war-time nuclear safety established by the IAEA, which states that nuclear facilities must maintain reliable communication with regulators and outside authorities.