Last October a mysterious radioactive cloud spread over Europe [1,2]. The source was traced to the Ural mountains between Russia and Kazakhstan. Although the amount of radioactive fallout in Europe was minuscule and harmless, there must have been a significant amount of radioactive material released at the source.
A few months ago, Putin announced Russia developed a nuclear powered missile with unlimited range [3] (really is was just 22 miles because "Russia"). The missile was reportedly tested in late 2017. Did Russia spew radioactive jet waste over their country during a field test of their nuclear powered missile?
A more likely explanation:
"The French IRSN has put forth the hypothesis in Jan-2018 that a possible reason for the release of Ru-106 radioactivity at Mayak-PA might be an unsuccessful attempt to extract the short-lived reactor-generated-isotope cerium-144 for the European/Italian nuetrino-detecton-project Borexino. Mayak-PA had agreed to deliver cerium-144 in early 2018, but canceled the contract in December 2017. Mayak PA was the only facility contractually-willing to attempt the extraction of cerium-144 from "fresh" spent nuclear fuel, 2–3 years old." [1]
Doesn't really sound plausible to me that a nuclear powered missile engine would, as far as I know, release a single radioactive isotope, Ruthenium 106 in this case, with its exhaust or upon a crash.
[1] https://en.wikipedia.org/wiki/Airborne_radioactivity_increas...