On the 25th of November 2018 three Ukrainian gunboats Berdyansk, Nikopol and Yany Kapu, crossed the Russian maritime border in the Kerch Strait and were seized by Russia because they did not respond to the legitimate request to stop.
Recurring pro-Kremlin disinformation about the November 2018 Kerch incident.
On 25 November 2018, border patrol boats belonging to Russia’s FSB security service seized two small Ukrainian armoured artillery vessels and a tug boat and their crews after shooting at them, wounding several Ukrainian servicemen and arresting 24. Russia argued that they were in Russian waters. The EU has urged Russia to release the captured crew.
However, the Kerch Strait and the Sea of Azov, as addressed by the 2003 bilateral agreement between Ukraine and Russia are defined as the internal waters of both Russia and Ukraine. The agreement gives both parties the power to inspect suspicious vessels. Furthermore, both the 2003 bilateral agreement and UN Convention on the Law of the Sea provide for the freedom of navigation.
At a meeting in Hamburg on 25 May, the International Tribunal for the Law of the Sea ordered Russia to immediately release 24 captured Ukrainian servicemen, and also to return to the control of Ukraine warships Berdyansk, Nikopol and Yany-Kapu. The court also stated that it did not find evidence of the Russian version of a provocation by Ukraine in the Kerch Strait.
More cases about the Kerch Strait incident are available here.