In just three months, three incidents of damage to Baltic Sea underwater cables have taken place. While accidential cable slices are common, the cluster raises suspicion.

Police say a Norwegian-owned and Russian-crewed ship that authorities suspect may have been involved in damage to an underwater fiber optic cable connecting Latvia and the Swedish island of Gotland has been stopped off Norway.

The Silver Dania cargo ship, a Norwegian vessel with an all-Russian crew, was boarded at the request of Latvian authorities with the help of coastguard, police said.

After a series of suspected undersea cable cuttings, NATO has launched a new surveillance and deterrence mission to protect critical infrastructure under the Baltic Sea.

NATO is ratcheting up its guard against suspected attempts to sabotage underwater energy and data cables and pipelines that crisscross the Baltic Sea.

The NATO military alliance is ramping up efforts to protect undersea cables in the region amid growing concerns of Russian sabotage and spying. View on euronews

Nato countries have stepped up patrols to protect critical underwater infrastructure in the Baltic Sea, which is bordered by eight countries, and other waters. A Royal Navy submarine was ordered to surface last November close to a suspected Russian spy ship which was loitering over undersea infrastructure in UK waters.

Estonia's defence minister on Wednesday said ships may have to pay a fee to use the Baltic Sea to cover costs of protecting undersea cables.

Baltic Sea as part of a mission to protect undersea cables and pipelines. As authorities investigate the fourth Baltic Sea cable-cutting incident in recent months, European leaders have expressed concern about the frequency of attacks involving civilian vessels and critical civilian infrastructure.