Ukraine’s Energoatom agency said the Zaporizhzhia complex was struck five times on Thursday, including near where radioactive materials are stored.

Axar.az reports that Russian-appointed officials, meanwhile, said Ukraine shelled the plant twice, disrupting a shift changeover, according to Russia’s TASS news agency.

In a statement ahead of a UN Security Council meeting called by Russia, Secretary-General Antonio Guterres warned that any damage could lead to “catastrophic consequences” in the region and beyond.

“The facility must not be used as part of any military operation. Instead, the urgent agreement is needed at a technical level on a safe perimeter of demilitarization to ensure the safety of the area,” Guterres said in a statement.

UN nuclear chief Rafael Grossi told the Security Council that the military activity around Zaporizhzhia was “very alarming” and called on Ukraine and Russia to immediately allow nuclear experts to assess damage as well as evaluate safety and security at the complex because the situation had “been deteriorating very rapidly”.