Whether it's true or not, it does not justify what Putin is responsible for in Ukraine.
(I'm not sure whether your comment was trying to soften the Russian invasion of Ukraine or not, but any attempted justification is no justification at all).
Not to side step into a full on political discussion. The conflict has been going on since 2014. If it did turn out the Ukraine was developing biological weapons to target Russians, it would definitely bolster Putins justification for invading. I'm not sure you though this through.
Same way the US used Iraqi mobile labs to justify its invasion and the seeking of regime change in Iraq, with arguably more deadly to civilian tactics like "Shock and Awe".
Moreover, if biological weapon will target Russians only (by asking them a question in the Russian language, I suppose) then it's completely legal for Ukraine to use such biological weapon to defend itself against Russian aggression. Madness is an important part of MAD.
You know that Putin is the guy that approves killing using Polonium and Novochok, right? Russia also has got labs with all kinds of viruses, which will cause global disaster if they ever leak. Where are these biolabs, BTW? In the center of Kiev? Because that's what they're bombing.
