The information came amid suspicions that Russia is deploying Iskander missiles in its Kaliningrad exclave and a series of airspace incursions by Russian military planes into Finnish and Estonian airspace.
Activity was being noted on land as well as at sea and in the air, the ministry said.
"For several days increased Russian military activity has been observed close to the borders of the Baltic countries," the statement said.
"At Brest in Belarus a joint Special Operations Forces and Russian paratroops exercise involving more than 1,000 soldiers and vehicles has started.
"In addition, adjacent to Latvia the 76th Guards Air Assault Division and 98th Airborne Division are training with full combat equipment, to capture an enemy airfield. At the same time 76th Division Commander Major General Alexei Naumeca has announced that the Division has received 10 tanks, giving it heavy tank capability for the first time."
In addition Russian missile brigades are drilling with rockets and artillery in the western military district while further away in the central military district strategic missile crews are being put through their paces.
some of the activity was reported on the official webpage of the Russian ministry of defense, as well as details of a major recent exercise by attack helicopters based close to the Latvian border in Pskov oblast.
Several planes have been identified near the Latvian border in recent days, with the Latvian National Armed Forces (NBS) confirming another ID on Saturday, this time of an An-12 plane in neutral waters not far from Latvia's sea border.
08.10. patruļlidmašīnas virs Baltijas jūras neitr. ūdeņiem pie LV terit. jūras robežas identificēja Krievijas BS lidmašīnu An-12.
— NBS (@Latvijas_armija) October 8, 2016
Due to the situation, NBS personnel were being maintained at state of increased readiness, the ministry said.
Unofficial sources continued to note signs of increased Russian military activity in the Gulf of Finland on Saturday.
Heavy traffic on RUAF strategic AF voice net
— Latitude 67N SIGINT (@Sigint67n) October 8, 2016