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.

A Norwegian ship suspected of being involved in "serious damage" to an underwater telecoms cable between Latvia and Sweden has been boarded by police.

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.

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.

Swedish authorities have seized a ship suspected of damaging a data cable running under the Baltic Sea to Latvia.Prosecutors said an initial investigation pointed to sabotage, and an inquiry has been launched involving Sweden's police,

Norway has detained the Silver Dania on suspicion of involvement in damaging a fiber optic cable in the Baltic Sea. The ship's crew are Russians, Dagbladet reports. Norwegian police said they had seized the Silver Dania based on a legal request from Latvia and a court order.