Ukraine’s Zaporizhzhia Nuclear Power Plant, Europe’s largest atomic power station, spent hours operating on emergency diesel generators on Monday after losing its external power supply for the seventh time since Russia’s full-scale invasion of its neighbor, the head of the UN nuclear watchdog said.

“The nuclear safety situation at the plant (is) extremely vulnerable,” Rafael Grossi, head of the International Atomic Energy Agency, said in a tweet. Hours later, 
national energy company Ukrenergo said on Telegram that it had restored the power line that feeds the plant.