The cable breaks in the Baltic Sea could be a deliberate act, the Norwegian prime minister said, according to the local media on Monday. “The reports of cable breaks in the Baltic Sea are very serious and worrying. It could be a deliberate act, a hybrid threat,” Jonas Gahr Store told the daily Verdens Gang.

Finnish police have discovered traces on the bottom of the Baltic Sea stretching for dozens of kilometers. It is believed that a tanker, which was carrying Russian oil, severed a power line and four telecommunications cables with its anchor,

NATO said on Friday it would boost its presence in the Baltic Sea after the suspected sabotage this week of an undersea power cable and four internet lines, while alliance member Estonia launched a naval operation to guard a parallel electricity link.

NATO will strengthen its presence in the Baltic Sea following the outage of the Estlink 2 submarine power cable, Secretary General Mark Rutte said on Friday after speaking to Finnish President Alexander Stubb.

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.

NATO said on Friday it would boost its presence in the Baltic Sea after the suspected sabotage this week of an undersea power cable and four internet cables, while alliance member Estonia launched a naval operation to guard a parallel electricity link.

NATO Secretary General Mark Rutte said on Dec. 27 that "NATO will enhance its military presence in the Baltic Sea" following the recent damage to the Estlink 2 power cable in the Gulf of Finland likely caused by Russia.