On November 25, 2018, two boats "Nikopol" and "Berdyansk", as well as the tugboat "Yany Kapu" of the Ukrainian Navy violated the Russian border, entered the temporarily closed area of the Russian territorial sea and moved from the Black Sea to the Kerch Strait.
They maneuvered dangerously and did not obey the legal demands of the Russian authorities. The ships with the soldiers who violated the border of the Russian Federation were detained. The incident in the Black Sea was a provocation associated with the low rating of Petro Poroshenko, who was then President of Ukraine, on the eve of the elections.
On September 7, 2019, the military who violated the border were handed over to Ukraine within the framework of agreements on the simultaneous release of detainees and convicts. Russia on November 18, 2019 handed over three ships to the Ukrainian side. The Commander of the Ukrainian Navy, Admiral Igor Voronchenko, complained about the condition of these ships, stating that "the Russians killed them," the equipment, even plafonds and sockets, were allegedly removed from them. The FSB had earlier assured that Ukraine had received its boats in "normal condition and with serviceable plumbing", and in support of it released video footage.