They tried to find out what they had found and it turned out that the sensors contained plutonium-239 used for fire alarm systems. Each sensor is a source of Alfa-radiation and contains one millicurie of plutonium-239. Such sensors are not produced in Russia anymore.
According to the deputy main health inspector of Chelyabinsk region Eleonora Kravtsova, the sensors could be dumped from any enterprise due to the negligence of the management. The found devices were delivered to the Mayak plant in Ozersk. The local police launched investigation, ITAR-TASS reported.