MOSCOW, April 18. /TASS/. The Baltic Sea Fleet forces are on duty after a NATO group of 4 ships entered the Baltic Sea on Thursday, the Russian National Defense Management Center reported.

The NATO group consists of the US guided missile destroyer USS Gravely, the Polish frigate ORP General Kazimierz Pulaski, the Turkish frigate Gokova and the Spanish frigate Almirante Juan de Borbon.

"In order to work out a prompt response in case of potential incidents or accidents in the waters of the Black Sea, the Baltic Sea Fleet forces are tracking the NATO ships. Ship strike groups, the Bal and Bastion coastal defense missile systems, as well as navy jets are on duty in the designated regions," the statement reads.

Since the beginning of 2019, the Baltic Sea Fleet forces have already carried out these activities on a number of occasions following NATO ships entering the Baltic Sea. On January 21, 2019, the US guided missile destroyer USS Gravely along with the Arleigh Burke-class destroyer USS Porter already sailed into the Baltic Sea. The Russian fleet’s corvettes Boikiy and Soobrazitelnyy tracked the US ships then. On February 26, USS Gravely again entered the Baltic Sea.