EE-S1

EE-S1 is a submarine communications cable between Sweden and Estonia. The cable is 240 km in length and it has three landing points – Kärdla (Estonia), Tallinn (Estonia) and Stavsnäs (Sweden). It became operational in June 1995. EE-S1 is owned by the Swedish pension fund AP-fonderna through its ownership in Arelion. Arelion was previously called Telia Carrier and was part of Telia Group.

Cable damage
In the afternoon of 7 October 2023, the cable was damaged. Four of the total six fiberoptic cable pairs were totally destroyed and the remaining two were functional. The location of the damaged cables is 70–80 meters below the sea surface according to the Swedish Navy.

On 17th of Oct 2023, the damage was made public when Swedish government reported the incident. Just a few hours later, the Balticconnector gas pipeline between Estonia and Finland was ruptured. Another submarine communications cable between Finland and Estonia was damaged at approximately the same time. Antti Kaikkonen was quoted saying "There are a bit too many coincidental coincidences for it to be coincidental".

In Estionia, investigation is carried out by KAPO, The Prosecutor's Office and Keskkriminaalpolitsei, and by Keskusrikospoliisi in Finland. Swedish submarine rescue ship HSwMS Belos (A214) is assisting in the investigation. Investigation revealed that the damage was clearly man-made.

Russian cargo ship Sevmorput and Chinese cargo ship Newnew Polar Bear are suspected to be involved in the incident. Both ships travelled near EE-S1 precisely at the time of damage. Sevmorput's owner Rosatom denied involvement.

The same two ships also travelled near the Balticconnector precisely at the time of damage, when Norwegian seismic institute Norsar detected seismic waves. The same two ships also travelled near the other damaged submarine communications cable between Helsinki and Tallinn.

After the incidents, both ships travelled in pair to Northern Norway, an area dense with undersea cables and gas pipelines. Norwegian Armed Forces reprioritised part of its activities to maritime surveillance. The seas in Northern Norway are heavily patrolled, but Norwegian Armed Forces declined to provide any comments to the media.

Conclusions


Investigation concluded that the cable was damaged by external force, with clear marks visible on the seafloor next to the cable.