MOSCOW, June 27. /TASS/. Two nuclear power plants in northwestern Russia - the Leningrad NPP and the Kola NPP - operate normally, with radiation levels being within the norm, a spokesperson for Rosenergoatom Concern (part of the Rosatom state nuclear energy corporation) told TASS.

"Both stations are working in normal regime. There have been no complaints about the equipment’s work. Aggregated emissions of all specified isotopes in the above-mentioned period did not exceed the reference numbers. No incidents related to release of radionuclide outside containment structures have been reported," the company said.

Several media outlets reported on Friday that nuclear and radiation security agencies of Sweden, Norway and Finland detected a slight increase in nuclear isotopes in the atmosphere above northern European territories. The isotopes were characterized as reactor-produced.

"Radiation levels at both NPPs and surrounding areas remained unchanged in June, and no changes are also observed at present. It remains at levels that correspond to normal work of reactors. Those levels do not exceed natural background radiation figures," Rosenergoatom said, adding that no incidents have been reported at the Leningrad and Kola NPPs.

Meanwhile, Executive Secretary of the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) Lassina Zerbo said in a Twitter post that stations of the CTBTO International Monitoring System detected a slight increase of several isotopes in the northwestern European airspace.

"[On] 22 /23 June 2020, RN IMS station SEP63 Sweden detected 3 isotopes: Cs-134, Cs-137 & Ru-103 associated with nuclear fission at higher than usual levels (but not harmful for human health)," the official said, attaching the map showing the spread of the isotopes.