Finnish authorities said they had boarded and taken control on Thursday of an oil tanker travelling from Russia, on suspicion it had caused the outage on Wednesday of an undersea power cable and three internet lines connecting Finland and Estonia.
The Cook Islands-registered ship, named by authorities as the Eagle S, was boarded by a Finnish coastguard crew which took command in the Baltic Sea and sailed the vessel to Finnish waters, a coastguard official told a press conference.
“From our side we are investigating grave sabotage,” said Robin Lardot, director of the Finnish National Bureau of Investigation, which leads the multi-agency probe.
“According to our understanding an anchor of the vessel that is under investigation has caused the damage,” he added.
The Finnish customs service said it had seized the vessel’s cargo and that the Eagle S was believed to belong to Russia’s so-called shadow fleet of ageing tankers that seek to evade sanctions on the sale of Russian oil.
Both the Finnish and the Estonian governments will hold extraordinary meetings later on Thursday to assess the situation, they said in separate statements.