The NBS tweet cites both an unnamed Kilo-class submarine as well as the corvette Soobrazitelny 531 as the two military ships seen today by the P-05 coast guard patrol boat about 5 nautical miles from Latvia's maritime territories. The Skrunda tracked the Russian warships for several hours until they exited from Latvia's Exclusive Economic Zone (EEZ) waters.
LVA patrol boat P-05 on 18 AUG spotted RU Navy Kilo-class submarine and ship Soobrazitelny 531 close to LVA territ. waters.— NBS (@Latvijas_armija) August 18, 2014
According to Russian news and information agency Ria Novosti, which reported on its putting-into-service launch in 2011, the Soobrazitelny 531 corvette carries a "formidable" array of armaments: an Uran anti-ship missile system, an AK-630M surface-to-air artillery unit, an A-190 automatic artillery system plus multiple torpedo tubes.
To jam and protect itself against homing missiles the Soobrazitelny features a radioelectronic suppression system. The system actively jams incoming missiles and can guide an enemy warhead to a decoy target.
A KA-27PL anti-submarine helicopter is also based on the corvette to seek and attack submarines.
Also on August 8 the corvette Stoiky and sea-going tugboat Victor Konetsky were identified 12 nautical miles from Latvia's maritime territory near Ventspils by a P-09 coast guard patrol boat.
Prior to that, on August 4 the NBS patrol boat P-09 sighted the corvette Stereguschiy as well as an unnamed Kilo-class submarine 5.7 miles from Latvia’s maritime territories.
Two months earlier naval forces also encountered the Soobrazitelny in neutral waters just off Latvia's maritime territories on June 24. The vessel was tracked further by the British navy’s coastal patrols off of Denmark’s shores during the BALTOPS multinational training exercises held in June.
These latest maritime encounters with Russia’s intimidating military come amongst a spate of NATO Baltic Air Policing (BAP) plane-scrambling incidents to intercept Russian Armed Forces jets and transport aircraft spotted in the skies over the Baltic Sea.