Russia tried to provoke Ukraine into returning fire during the attack in the Kerch Strait to start overt aggression.
Russia's War Against Ukraine
UkrInform: Defense Minister Poltorak claims Ukraine won’t give up its right to pass through Kerch Strait
This video grab taken from footage of local media Kerch Info on Nov. 25, 2018 shows Russian aircraft flying over the Crimean Bridge that spans the Kerch Strait, a narrow strip that links the Azov and Black seas, as a Russian ship blocks the strait, after Russia fired on and then seized three Ukrainian ships on Nov. 25, accusing them of illegally entering its waters in the Sea of Azov.
