Nordic authorities say they detected slightly increased levels of radioactivity in northern Europe this month may be from a source in western Russia, while the Russian officials say their plants operate normally and no problem has been reported. 

Iran PressEurope: Russian news agency TASS, citing a spokesman with the state nuclear power operator Rosenergoatom, reported that the two nuclear power plants in northwestern Russia haven't reported any problems.

The Leningrad plant near St Petersburg and the Kola plant near the northern city of Murmansk, "operate normally, with radiation levels being within the norm," Tass said.

The Swedish Radiation Safety Authority said on Tuesday that "it is not possible now to confirm what could be the source of the increased levels" of radioactivity or from where a cloud, or clouds, containing radioactive isotopes that have allegedly been blowing over the skies of northern Europe originated. Its Finnish and Norwegian counterparts also haven't speculated about a potential source.

The National Institute for Public Health and the Environment in the Netherlands said Friday it analyzed the Nordic data and "these calculations show that the radionuclides (radioactive isotopes) come from the direction of Western Russia."

The unnamed Rosatomenergo spokesman told Tass on Saturday that radiation levels at the Leningrad and Kola power stations and their surrounding areas "have remained unchanged in June, and no changes are also observed at present."

"Both stations are working in the normal regime. There have been no complaints about the equipment's work," Tass quoted him as saying. "No incidents related to release of radionuclide outside containment structures have been reported."

The Finnish, Norwegian, and Swedish radiation and nuclear safety watchdogs said this week they've spotted small amounts of radioactive isotopes harmless to humans and the environment in parts of Finland, southern Scandinavia and the Arctic. 212/ 104

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