Earlier this month, NATO launched a new mission, “Baltic Sentry,” to enhance surveillance and deterrence in the Baltic Sea. The operation includes frigates, maritime patrol aircraft, and naval drones, with a focus on protecting undersea assets.

Russia says it's withstanding the impact of sanctions. Sweden's finance minister says satellite images show a different story.

The Arelion submarine cable, which connects the Swedish island of Gotland to Lithuania, and the C-Lion 1 submarine communications cable that runs between Finland's capital Helsinki and the German city of Rostock were also damaged in mid-November near Sweden's territorial waters.

Swedish authorities have seized a ship suspected of damaging a data cable running under the Baltic Sea to Latvia. The Vezhen - a Maltese-flagged ship - is now anchored outside the Swedish port of Karlskrona.

Sweden's coastguard has intercepted a Bulgarian ship after fiber optic cables between Sweden and Latvia were damaged. Suspected sabotage of such undersea links in the Baltic Sea has been blamed on Russia.

Swedish authorities said late on Sunday they are detaining a vessel suspected of “gross sabotage” following the damage of an undersea communication cable in the Baltic. “Concrete investigation measures” are being carried out on board the ship, the Swedish prosecutor office said in a statement.

Sweden on Sunday said it had seized a ship suspected of having damaged a fibre-optic cable under the Baltic Sea linking the country to Latvia, which sent a warship to investigate the latest apparent act of sabotage.