And what is the source? Honest Ukrainian word? But anyway.

"Germany’s BND foreign intelligence agency said Russia has been using not only tear gas but also "the more dangerous chemical chloropicrin, which can be lethal in high concentrations in enclosed spaces". This is a more serious violation of the Chemical Weapons Convention, it added."

So using tear gas is a violation of the Chemical Weapons Convention? Like London police using tear gas to disperse protesters? [0]

"The chemical [chloropicrin] ... can cause irritation of the lungs, eyes and skin and can cause diarrhoea, vomiting and nausea. "

But "chemical weapons" make such a good headline.

[0] https://www.london.gov.uk/who-we-are/what-london-assembly-do...]