A Norwegian-owned and Russian-crewed ship that authorities initially suspected may have been involved in damage to an underwater fiber optic cable connecting Latvia and the Swedish island of Gotland has been released.

A ship with a Russian crew that was briefly held on suspicion of being involved in cable damage in the Baltic Sea has been released by the Norwegian authorities. Police in the northern Norwegian city of Tromsø announced on Friday that there was no evidence that the Silver Dania ship had anything to do with the recent damage to a fibre optic cable between Latvia and Sweden.

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.

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.

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.

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.