VIENNA, Austria (AFP) — An overnight strike has cut off external electricity supply to the Ukraine’s Russian-occupied Zaporizhzhia nuclear power plant, Europe’s largest, the United Nations nuclear watchdog said on Thursday. 

No release of radioactivity was detected and radiation levels remained normal, the International Atomic Energy Agency (IAEA) said in a statement.

The plant “is currently relying on emergency diesel generators to power the cooling of its six shut-down reactors and maintain other essential nuclear safety functions,” it said.

The strike at 9 p.m. on Wednesday hit an electrical substation that supplies the plant. It was the 19th time the plant had lost its off-site power supply since the start of the war in February 2022, the agency said.

“The latest loss of off-site power once again highlights the extreme fragility of the electrical grid and the constant dangers to nuclear safety during the war,” IAEA chief Rafael Grossi said.

The plant is currently preparing to repair its main power line, which has been offline since 24 March.

Zaporizhzhia is Europe’s largest atomic energy plant, lies close to the frontline in southern Ukraine, and was captured by Russian troops in the early days of their 2022 invasion.

Moscow and Kyiv have repeatedly accused each other of risking a nuclear catastrophe with attacks near the plant.