Zaporizhzhia Nuclear Power Plant, which is surrounded by Russian forces, has lost all external power necessary for crucial safety systems for the second time in five days.

On Wednesday, the head of the UN's nuclear watchdog called it a "deeply worrying development."

The International Atomic Energy Agency's Rafael Grossi issued the warning during a flurry of unrest related to Russia's ongoing conflict in Ukraine.

According to the Association Press, Russia's main internal security agency said that eight people had been apprehended in connection with the weekend explosion on the Crimean bridge while the military command of Ukraine reported that its forces had retaken five communities in the southern Kherson area.

Europe's Largest Nuclear Facility Losing Energy

The largest nuclear power plant in Europe, the Zaporizhzhia Nuclear Power Plant, reported a loss of external power via IAEA monitoring.

Grossi, who met with Russian President Vladimir Putin on Tuesday, said the nuclear safety and security equipment was kept operational.

State-run nuclear company Energoatom of Ukraine said on the social media platform Telegram that a Russian missile strike on the substation "Dniprovska" in the neighboring Dnipropetrovsk area to the north damaged it.

UKRAINE-CHERNOBYL-NUCLEAR PLANT
(Photo : SERGEI SUPINSKY/AFP via Getty Images)
General view of the "sarcophagus" covering the destroyed 4th power block of Chernobyl's nuclear power plant 27 February 2006. Chernobyl's number-four reactor, in what was then the Soviet Union and is now Ukraine, exploded 26 April 1986, sending a radioactive cloud across Europe and becoming the world's worst civilian nuclear disaster. Following the accident, a concrete sarcophagus was built over the stricken reactor and a new 20,000-tonne steel case to cover the whole plant is planned on being constructed between 2008 and 2009. The power station was eventually shut down 15 December 2000.

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The attack forced the diesel generators to automatically turn on and shut off a vital communication route to the plant.

According to Energoatom CEO Petro Kotin in an interview with the AP last month, the Zaporizhzhia facility typically only has enough fuel to power the diesel generators for 10 days. He said the generators were the station's final line of defense against a radioactive disaster.

An uptick in fighting in southern Ukraine and a recent assault of Russian airstrikes across the country coincide with growing concerns about the nuclear facility.

Kyrylo Tymoshenko, the deputy director of President Volodymyr Zelenskyy's administration, noted that at least 14 persons have died as a result of Russian airstrikes in the eastern Donetsk and Zaporizhzhia districts.

There were at least 34 injuries reported across five locations, he wrote in a Telegram post.

What Happens if It Explodes?

The Russian-controlled Zaporizhzhia nuclear power station in Ukraine might have a "nuclear disaster" because of shelling, IAEA said.

"If multiple catastrophic factors come together, an explosion might be possible," Ross Peel, the research and knowledge transfer manager for the Centre for Science and Security Studies at King's College London, told Al Jazeera.

Concerns have been raised regarding the shelling that is taking place in the area of the complex, which has the potential to harm vital infrastructure, including the reactors.

MV Ramana, a professor at the School of Public Policy and Global Affairs at the University of British Columbia, added that reactors require continuous cooling from water flowing through them.

If the water supply is interrupted, reduced, or cut off in any other way, the reactor may lose cooling, which will cause the fuel to melt. The object could explode because of the huge pressure that will be created.

Experts predicted that, in the immediate wake of an explosion, there would likely be extensive evacuations to avoid an impenetrable radioactive cloud. However, the effects of a radioactive leak would likely not be felt for many years.

Acute radiation poisoning or later-emerging malignancies may be among the diseases.

This occurs over a period of days, weeks, or even months. It's possible that more cancer cases will develop in the years to come for those who were exposed to lesser doses of radiation.

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