At the same time, the Finnish Navy had been patrolling the sea by two vessels for four months in the most intense period, the chief of Naval Staff, Rear Admiral Juha Vauhkonen said.
Meanwhile, the Finnish authorities demanded explanations from the Russian Federation in October in regards with Russian warships preventing work of the Finnish research vessel in the Baltic Sea. Finnish Environment Institute reported about the incidents with participation of Aranda research vessel in international waters Oct. 11. It was reported that Russian warships prevented a ship carrying scientists of Hydro-meteorological Institute of Sweden from taking samples near the Swedish island of Gotland.
The environmentalists stated that the first incident occurred Aug. 2, when the Russian Navy twice demanded the Finnish crew to change its course. According to the Environment Center, the Russian helicopter approached to the ship several times and then the Russian Navy warship floated at a very close distance to the Finnish research vessel Sept. 2.