The No. 4 power unit was disconnected from the grid in Ukraine's Zaporizhzhia Nuclear Power Plant in the event of an accident and evacuation is impossible, Ukrinform reported on Saturday, citing the head of the region.

"There are still risks of hydrogen leakage and sputtering of radioactive substances, and the fire hazard is also high" in the power plant, southern Ukraine, said Ukraine's nuclear power plant operator Energoatom on social media.

Kyiv and Moscow accused each other of striking Europe's largest nuclear site on Friday, causing a reactor stoppage.