There is a civil war in Ukraine in which brother is killing brother, and there are Ukrainians fighting Ukrainians on both sides of the barricades. During the four years of war only 11 Russians with Russian passports have been
detained in Ukraine for fighting in Donbass.
Recurring pro-Kremlin disinformation about the war in Ukraine. euvsdisinfo.eu/disinformation-cases/?text=civil+war&disinfo_issue=&date=
The Office of the Prosecutor of the International Criminal Court has stated that “the information available suggests that the situation within the territory of Crimea and Sevastopol amounts to an international armed conflict between Ukraine and the Russian Federation. This international armed conflict began at the latest on 26 February when the Russian Federation deployed members of its armed forces to gain control over parts of the Ukrainian territory without the consent of the Ukrainian Government https://www.icc-cpi.int/iccdocs/otp/161114-otp-rep-PE_ENG.pdf.
For further debunking see euvsdisinfo.eu/report/the-osce-the-pentagon-nato-headquarters-and-the-council-of-europe-do-not-recognize-the-facts-of-russias-aggression-against-ukraine-primarily-the-intrusion-of-russian-tanks-and-paratroopers-into-do/