Helsinki, 27 December 2024 (dpa/MIA) - Finnish authorities have boarded an oil tanker in the Baltic Sea as part of an investigation into the outage of a subsea electricity cable between Finland and Estonia.

Police in Helsinki said on Thursday that the Cook Islands-registered Eagle S tanker was seized by maritime authorities and that they had taken control of the vessel.

The operation came a day after the EstLink2 power cable was knocked offline. Other communication cables in the same waters were also damaged.

Possible connection to Russia

Finnish President Alexander Stubb suggested the freighter is part of Russia's shadow fleet – that is, ships that Russia use unofficially to circumvent sanctions, for example, to deliver its oil to other countries.

"It is necessary to be able to prevent the risks posed by ships belonging to the Russian shadow fleet," Stubb wrote on X after meeting with police and border guard chiefs on Thursday.

According to investigators, the damage to the cable could have been caused by the ship intentionally dragging its anchor.

Finnish grid operator Fingrid said that the repair would take several months but that power supply in Finland is stable. In Estonia, the Ministry of Economic Affairs said there has been no impact to customers so far.

The European Commission, the executive arm of the EU, said it condemned "any deliberate destruction of Europe’s critical infrastructure."

"The suspected vessel is part of Russia’s shadow fleet, which threatens security and the environment, while funding Russia’s war budget. We will propose further measures, including sanctions, to target this fleet."

Damage to two other subsea cables

Undersea cables are prone to faults, often caused by accidents such as ship anchors. But these pieces of critical infrastructure can also be the target of covert military operations.

In November, damage occurred to two fibre-optic cables in the Baltic Sea within a short period of time. One of the cables runs between Sweden and Lithuania and the other between Finland and Germany.

The Swedish authorities are investigating possible sabotage. The investigators are focusing on a Chinese ship called Yi Peng 3, which is thought to have passed near the cables at the time of the outage.

Last year, a Balticconnector gas pipeline between Finland and Estonia was severely damaged.

Photo: Finland's maritime authorities/X