Ukraine said on Friday it had bombed a Russian base in the town of Energodar, near the Zaporozhye nuclear power plant (NPP) which is being assessed by United Nations inspectors due to safety concerns.

"Targeted strikes by our troops in the localities of Energodar and Kherson have destroyed three artillery systems of the enemy as well as an ammunition depot," the Ukrainian army said.

A team of 14 inspectors from the UN’s nuclear watchdog, the International Atomic Energy Agency (IAEA), is visiting Zaporozhye — Europe’s largest nuclear power plant — as global concern grows over its safety in a war raging ever-closer to its six reactors.

IAEA would retain a permanent presence there at Zaporozhye NPP

UN inspectors spent their second day at Zaporozhye on Friday. At least two members of the team will remain there on a permanent basis to ensure its safety.

IAEA head Rafael Grossi said on Thursday the site had been damaged by the fighting in Ukraine.

"It is obvious that the plant and physical integrity of the plant has been violated several times," he said when he and part of his team returned from the NPP to Ukrainian-controlled territory after a first visit lasting around three hours.

Grossi said some of his inspectors would stay at the plant "until Sunday or Monday" to "dig deeper" into some of the observations the team had made and said the watchdog would retain a permanent presence there.

"We have achieved something very important today, and the important thing is the IAEA is staying here," he said.

Russia welcomes IAEA arrival at Zaporozhye NPP

Russia’s envoy to Vienna, Mikhail Ulyanov, said six IAEA inspectors had stayed behind and that two more would remain there "on a permanent basis."

"We welcome this because an international presence can dispel the many rumors about the state of affairs at the nuclear power plant," he told Russian news agency RIA Novosti.

The Kremlin described the inspectors’ arrival at the plant as "very positive".

"In general, we are very positive about the fact that, despite all the difficulties and problems … the commission arrived and started to work," Spokesperson Dmitry Peskov told reporters.

Only one of the six reactors working at the NPP

A shelling attack at dawn on Thursday forced one of the plant’s six reactors to shut down and a backup power supply got damaged.

Energoatom said the NPP's emergency protection system kicked in, shutting reactor five. That left only one of the six reactors working.

Red Cross Director General Robert Mardini on Thursday warned the consequences of hitting the plant could be "catastrophic", underlining that "the slightest miscalculation could trigger devastation that we will regret for decades."

"It is high time to stop playing with fire and instead take concrete measures to protect this facility … from any military operations," he told reporters in Kiev.

Ukraine has also accused Russia of storing ammunition at the Zaporozhye NPP and deploying hundreds of soldiers there.

No Russian heavy weapons at nuclear site: Moscow

Earlier, Russian Defense Minister Sergei Shoigu declared that Russian armed troops, contrary to accusations by Kiev, are not using the Zaporozhye NPP for military objectives, adding that the IAEA's ongoing mission would hopefully confirm this.

During a working conference, the Russian top defense official revealed that 29 strikes were launched against the NPP in Energodar on July 18. He stated that 120 artillery shells and 16 kamikaze drones were employed.

Shoigu dismissed as "blatant lies" the Ukrainian claims that Russia was using the facility to attack Ukrainian positions "with long-range artillery systems."

Ukraine's President Voldomyr Zelensky claimed that Russia was attempting to turn the IAEA mission "into a fruitless excursion," and accused IAEA head Rafael Grossi of failing to secure access to the station for a group of "independent journalists" who wanted to accompany the Ukrainian inspectors.

"We hope that the mission will make objective conclusions from the situation at the plant nevertheless," Zelensky said in a video address on Thursday evening.

He added that Ukraine’s goal was the "demilitarization" of the Zaporozhye site. Moscow earlier stated that it would not accept a complete withdrawal of soldiers from Energodar because it did not trust Kiev to do the same.

The Russian Defense Ministry revealed on Thursday that an amphibious commando operation thwarted a Ukrainian effort to capture the NPP.

Kiev reports that Russia is behind the attacks on the NPP, with the stated intention of "tarnishing Ukraine's reputation."

During the Friday meeting, Shoigu emphasized that by bombing the Zaporozhye NPP, Kiev risks a nuclear tragedy. He also accused the US and the EU of "hushing up" Ukraine's role, and "encouraging" Kiev to unleash additional strikes.

"All responsibility for possible emergencies caused by possible future provocations will lay on the Ukrainian authorities," he warned.

Russian forces have had complete control over the Zaporozhye NPP since March, but drone attacks by Ukrainian forces have regularly targeted the facility, leading Russia to request help from the IAEA to address security issues.

The head of the Russian National Defense Control Center, Colonel General Mikhail Mizintsev, pointed out that the Russian Defense Ministry is considering the shelling of the Zaporozhye NPP by Ukrainian forces an act of nuclear terrorism under a UN convention adopted by a resolution of the UN General Assembly. 

The official said if an accident were to happen, which the shelling could potentially cause, the effects would surpass the scale of Chernobyl and Fukushima - the entire territories of Ukraine, Donetsk, Lugansk, Russia, Belarus, Moldova, Bulgaria, and Romania would be contaminated by nuclear waste.

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