They don't exist.
Russia may try to seize them. (therefore they exist)
They don't exist but Russia may try to cook a bio-weapon on the fly after seizing biomedical labs.
Why would Russia bother creating one in Ukraine though. Like many other countries Russia has bio-weapon labs, they already have potent vectors.
And though the "Chernobyl turned into a dirty bomb" scenario was pretty retarded to begin with, the "bio-weapons" one is even more so.
Anyway, that was a conspiracy last week.