Because the Ukrainians have released similarly inflammatory statements before and they have had to walk them back. See the “Russians are shooting at an active nuclear reactor and are going to kill us all” story they released, then had to walk back to use one infamous example.
Because the Ukrainians have released similarly inflammatory statements before
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Just because an “inflammatory” statement is released by one party does not make it propaganda; it could well be a report made in error, but believed to be true at that moment.
Propaganda is a repeated unwavering theme, including repeatedly creating fallacious and obvious myths, not a one time report.