The oil tanker which is thought to have severed an undersea power cable connecting Finland and Estonia in the Baltic Sea in December was spotted near the site of a telecommunications cable located near the Wadden island of Terschelling a year earlier, the NRC has found.

The Eagle S’s automatic identification system (AIS) put it in the North Sea at some 50 kilometres of the island in November 2023, where it stayed for a couple of hours, the paper said.

The signals showed that on November 24 the tanker had been headed in a northeasterly direction before suddenly changing course to the location of the Atlantic Crossing 1, a telecommunications cable linking the United States to Britain, the Netherlands and Germany. It then sailed back and forth over the site for the next two hours.

According to a source of shipping website Lloyd’s List, the tanker was “loaded with spying equipment” and “sensor-like equipment” had been dropped overboard.

The actions of the tanker are “suspicious, without a doubt”, Rob de Wijk, professor of international relations and initiator of the The Hague Centre of Strategic Studies (HCSS) told the paper.

De Wijk said that the fact that Dutch undersea infrastructure is situated outside the territorial waters where the government has little jurisdiction is putting it at risk of sabotage. The escalating conflict between Ukraine and Russia is increasing the tensions at sea, he said.

The Cook-Islands registered Eagle S, which is thought to be part of a ghost fleet of oil tankers used by Russia to circumvent sanctions, has been impounded by Finnish coast guard pending the result of an investigation into the events in the Baltic. Its crew has also been detained. The Finnish authorities also suspect Russia to have been involved in the alleged sabotage.