According to the Ukrainian defence ministry, two Ukrainian armoured artillery boats and a tugboat were fired at, rammed, and then seized by Russian forces. Russian Navy Spetsnaz boarded the damaged vessels and captured their crews. Firsthand reports stated that at least two Ukrainian sailors have been wounded in action. The two armoured artillery are the Berdyansk and the Nikopol, the tugboat is the Yani Kapu.

According to a Ukrainian Navy spokesperson, the three vessels were intending to cross into the Sea of Azov through the Kerch Strait, a narrow water lane situated between Crimea and the Russian mainland.  The vessels began their journey from the Black Sea port of Odessa and were heading to the Ukrainian port of Mariupol. Since tensions erupted in 2014, Russia has been monitoring the Kerch Strait closely, at times even shutting it off. The Russian Navy is currently using a tanker to completely shut off the Strait.

Moreover, Russian Air Force Su-25 fighter jets and Kn-52 helicopters are patrolling the area. The Su-25 is often used in a Close Air Support role. Additionally, both aircraft can carry anti-ship missiles — reportedly even the Kh-35 missile, a subsonic projectile that could easily sink a small ship (for example, a frigate) or seriously damage a large one (for instance, an aircraft carrier).