Russia has nearly tripled its military manpower in Crimea since illegally annexing the peninsula in 2014, an intelligence report says, in preparation for possible further incursions into Ukraine.

Russian forces have dramatically increased across the board, the Estonian Foreign Intelligence Service found, with large numbers of personnel, armor, artillery, aircraft, and ships moved to the formerly autonomous republic located in Ukraine's south.

"The purpose of strengthening the forces is to position Russian units and equipment for possible offensive operations deep into Ukraine in the event of a broader confrontation, and effectively prevent the arrival of international assistance into the country," states the 2019 International Security and Estonia report .

Russia raised its troop numbers in Crimea from 12,500 to 31,500 between 2014 and 2018, the report said, citing statistics from open source intelligence site InformNapalm. Armored vehicles increased from 92 to 583, while artillery systems rose from 24 to 162. The number of airplanes has increased nearly sixfold, from 22 to 122.

The Russian Navy has also significantly increased its presence there, with the number rising from 27 to 78. Russia has long maintained a port in Crimea, which it considers crucial to its security interests in the Black Sea.

Russian forces initially invaded Crimea with unflagged “little green men,” but they have since become more brazen as their presence in the region has grown. In November, the Russian Navy and border guard fired on Ukrainian warships attempting to pass through the Kerch Strait off the coast of Crimea, taking 24 Ukrainian sailors prisoner.

In April, Russian aircraft repeatedly buzzed the USS Donald Cook, coming into dangerously close proximity of the American destroyer.

International observers witnessed entire Russian Army columns entering occupied eastern Ukraine last year and discovered Russian electronic warfare systems there earlier this year.

Estonia, a NATO member located in Europe’s Baltic region, is on the front line against Russian aggression. Estonian officials have complained for years about Russia targeting their country with misinformation attacks and propaganda. While comparatively small, Estonia has become hyper-focused on Russian aggression since falling victim in 2007 to a massive cyberattack, which temporarily paralyzed banks, media, and government agencies. Estonia blames Russia for the attacks, though the Kremlin’s direct involvement has not been proven.

The United States has provided Ukraine with $1.5 billion in military support since the 2014 annexation, and the Pentagon plans to give the country another $250 million to buy various weapons and equipment. Russia, meanwhile, continues to support separatists in eastern Ukraine.