Russia has notified the International Atomic Energy Agency (IAEA) that suspected fragments of downed missiles were found close to the Kursk Nuclear Power Plant (Kursk NPP) amid the Ukrainian attack in Kursk city.

"On August 8, fragments and debris, presumed to be parts of downed missiles, were found at the site, including in the vicinity of the radioactive waste processing facility. Although there have been no confirmed reports of direct shelling on the city of Kurchatov, the nuclear power plant, or related energy infrastructure, the situation remains tense," Russia's permanent mission to international organizations in Vienna was quoted by TASS News Agency as saying on its official Telegram channel, reported Xinhua.

The mission said, "Ukraine's reckless actions not only threaten Russia's nuclear facility but also put the entire global nuclear industry at risk."

According to reports, Ukraine launched a massive attack on defence position in Kursk on Tuesday.

Russia has declared a state of emergency in Kursk.

The Russian defence ministry said it was “continuing to repel” Ukraine’s military, which it claimed had lost more than 280 personnel in the past 24 hours - a figure that has not been independently verified, reported BBC.

IAEA Director General says he is monitoring situation

IAEA Director-General Rafael Mariano Grossi said it has been monitoring the situation on the reported military activities taking place in the vicinity of the Kursk Nuclear Power Plant (NPP).

This NPP has six units of two different reactor types: RBMK-1000 and VVER-510.

Two of the RBMK-1000 are in shutdown and two are fully operational.

The two VVER-510 units are under construction.

"In view of the reportedly significant military activity, I wish to remind all parties of the seven indispensable pillars for ensuring nuclear safety and security during an armed conflict," Grossi said.

"Additionally, I emphasize the five concrete principles to help to ensure nuclear safety and security which have been established for the Zaporizhzhya NPP in the context of the current conflict between the Russian Federation and Ukraine, and which are equally applicable in this situation," he said.

"These include, among others, the imperative to ensure the physical integrity of a nuclear power plant. This is valid irrespective of where an NPP is situated," he said.

He appealed to all sides to exercise maximum restraint in order to avoid a nuclear accident with the potential for serious radiological consequences.

"I am personally in contact with the relevant authorities of both countries and will continue to be seized of the matter. I will continue to update the international community as appropriate," he said.

Meanwhile, the outgoing UN senior humanitarian official in Ukraine condemned a deadly Russian attack on Friday that killed and injured dozens in the eastern town of Kostiantynivka, in the Donetsk region.

"Civilians pay the highest price in this war," Denise Brown said in statement.  "We must not allow this to be normalized. International humanitarian law must be respected, and civilians and civilian infrastructure must be protected at all times."

According to the UN Office for the Coordination of Humanitarian Affairs (OCHA), increasing attacks in the Donetsk and Sumy regions over the past two days killed and injured many civilians and damaged infrastructure.

The attacks also heightened the needs of about 60,000 people in vulnerable communities, and mass casualties have affected people in the towns of Myrnohrad, Pokrovsk and Toretsk.

OCHA said aid workers continue to provide food, hygiene supplies, school materials, cash assistance, and legal and psychological support to affected civilians in the Donetsk region.