Occupying Russian forces are building an "unknown premises" on the Zaporizhzhia nuclear reactor site in Ukraine, the State Inspectorate of Nuclear Regulation of Ukraine wrote on its Facebook page Wednesday.

"The operation of the [nuclear fuel] site at the [reactor] is limited due to arbitrary construction started by the occupiers — the [Russian] State Atomic Energy Regulatory Commission," the post read. "The State Inspection of Nuclear Regulation of Ukraine established a violation of the requirements of the legislation of Ukraine, norms, rules, and standards, of nuclear and radiation safety at the site of the dry storage of spent nuclear fuel (SSFU), which is one of the seven nuclear installations at the Zaporizhzhia [nuclear power plant.]"

The agency said the "arbitrary construction of an unknown structure" by Russian forces and the denial of Energoatom company personnel having access to the site could pose a danger.

Energoatom wrote on its website Monday that the war has taken an environmental toll by "destroying an important ecological component" of the plant with the shutdown of warm water entering the "cooling pond" causing a drop in temperature of just 13 degrees, leading to a "mass fish die-off" of warm water tilapia and Asian catfish that destroy green algae and keep the cooling tubes clean.

"Under favorable conditions, when the temperature in winter never fell below 18 degrees above zero, the fish multiplied," the company's statement said. "So, if the water temperature in the cooling pond does not rise in the near term, about 1,000 tons of dead fish will be washed ashore."

The company posted on its Telegram social media account Oct. 18 that Russian soldiers "kidnapped" company workers and took them to an unknown location.

"Russian nuclear terrorists detained Oleg Kostyukov, the head of information technology service at the Zaporizhzhia NPP, and Oleg Osheka, the station's assistant general director, and took them to an unknown destination," the Telegram post read. "Currently, nothing is known about their whereabouts and condition."

The company appealed to International Atomic Energy Agency Director General Rafael Grossi and "the world community" to free the workers.

"We appeal to the Director General of the IAEA, Rafael Grossi, and the entire world community to make every effort and take all possible measures to free the ZANP workers from the captivity of Russian terrorists and facilitate their return to duty," the agency's post said.

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