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.

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.

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.

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.