The the 404-foot-long frigate Hetman Sahaydachniy / Photo from UNIAN

The flagship of the Ukrainian fleet, the 404-foot-long frigate Hetman Sahaydachniy, has entered the Black Sea to close an area for firing drills and carry out a number of combat training tasks.

"The crew had challenging tasks amid firing from an AK-100 [100mm] naval cannon and destroying the imaginary enemy from the AK-630, a 30mm automatic ship-based gun used against airborne targets, with which the personnel have successfully coped," the press service of the Ukrainian Navy said on Facebook on May 3.

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"For the first time in several years, the vessel conducted drills with the use of the PK-16 chaff decoy launching system to jam guided anti-ship missiles," it said.

What is more, Ukrainian military sailors recorded another violation of the law of the sea by the Black Sea Fleet of the Russian Federation, which is present in occupied and strategically important Ukrainian maritime sectors.

In addition to military reconnaissance ships of the Russian Federation, the flagship's crew saw a Russian tanker, which was moving from the Russia-occupied sea areas, lower the Russian flag so that it could not be identified by the Ukrainian side in the area of the Holitsynske gas fields, which were seized by Russia after it occupied Ukraine's Crimea in March 2014.