East StratCom disinformation claim:
The annexation of Crimea was necessary because the new Ukrainian authorities had planned to attack the base of the Russian fleet in Sevastopol and start a war against Russia.
Documentation for claim
Period/date: 15. February 2017
No evidence given. The annexation of Crimea by the Russian Federation took place in February-March 2014, almost two months before the pro-Russian protests in Donetsk and Luhansk oblasts escalated into an armed separatist insurgency http://www.bbc.com/news/world-europe-28969784. So this was clearly not a case of preventing the escalation of a conflict which had not even started.
Documentation for the debunk
This information is reported by Pavel Spirin, former journalist in Disinformation Review issue 59. The item is located at row number 33 in the report.