Sweden has opened a preliminary investigation into suspected aggravated “sabotage” and ordered the detention of a vessel in the Baltic Sea suspected of damaging an underwater fiber optic cable connecting Latvia and the Swedish island of Gotland earlier that day.

The attacks come as Estonia, Latvia, and Lithuania prepare to cut on February 8 their electricity links to Russia and Belarus.

Swedish authorities boarded a Maltese-flagged ship seized in connection with the latest breach of cables running along the bottom of the Baltic Sea to begin an investigation into the matter, the country's security police said on Monday.

Several undersea cables running under the surface of the Baltic Sea have been damaged in suspected sabotage incidents in recent months.

Russia has condemned the Western alliance for ramping up its naval presence in the so-called 'NATO lake' after alleged sabotage by Moscow-linked vessels.

Bulgarian bulker owner Navibulgar admitted that one of its ships may have cut an undersea cable in the Baltic Sea over the weekend, but dismissed suspicions raised by Swedish authorities that this could have been sabotage.

Another undersea cable has been broken in the Baltic Sea, this time between Swedish Gotland and Ventspils in Latvia. What do we know about the suspected sabotage?

The Vezhen was seized in Swedish waters, where it was anchored. The ship’s Bulgarian owners claim the damage was accidental, but authorities are investigating.

An undersea fiber optic cable between Latvia and Sweden was damaged on Sunday, likely as a result of external influence, Latvia said, triggering an investigation by local and NATO maritime forces in the Baltic Sea.

Latvia on Sunday said it had sent a warship to investigate the latest apparent act of sabotage in the Baltic, as Sweden reported at least one undersea optic fibre cable linking the two countries had been damaged.

One of Russia’s latest warships is holding large-scale live-fire drills in the Baltic Sea amid mounting regional tensions with NATO. “As part of the planned deployment to the sea, the...