A mysterious cloud containing radioactive ruthenium-106, which moved across Europe in autumn 2017, is still bothering Europe’s radiation protection entities. Although the activity concentrations were innocuous, they reached up to 100 times the levels of what had been detected over Europe in the aftermath of the Fukushima accident. Since no government had assumed responsibility, a military background could not be ruled out.
Click here for original story, Radioactive cloud over Europe had civilian background
Source: Phys.org