By Isabelle Yr Carlsson COPENHAGEN (Reuters) -Two undersea telecommunications cables that were damaged in the Baltic Sea on Dec. 25 appeared to have been torn apart by a strong external force, Finland's Elisa said on Monday,

Finnish police say authorities detained a ship linked to neighboring Russia as they investigate whether it damaged a Baltic Sea power cable and several data cables.

General Mark Rutte says the military alliance will step up patrols in the Baltic Sea area as Finnish investigators work to establish whether a ship linked to Russia sabotaged undersea cables there this week.

Finland's Elisa said on Monday that it had finished the repair of its two undersea telecommunications cables that were damaged in the Baltic Sea on Dec. 25. Finland on Dec. 26 seized the Eagle S tanke

HELSINKI – An undersea power cable linking Finland and Estonia broke down on Dec 25, Finland’s Prime Minister said, the latest in a series of incidents involving telecommunications cables and energy pipelines in the Baltic Sea.

Finland has seized the Eagle S, a Cook Islands-flagged oil tanker, as part of an investigation into severe damage to underwater cables in the Baltic Sea.

Finnish police said on Sunday they had found tracks that drag on for dozens of kilometres along the bottom of the Baltic Sea where a tanker carrying Russian oil is suspected of breaking a power line and four telecoms cables with its anchor.