After several incidents involving damage to underwater cables in the Baltic Sea, including the recent incident that Sweden has started investigating, NATO has created a program to monitor these vital communication and energy subsea pipelines.
Estonian warships had previously spent most of their time protecting the border, searching for stray mines at the bottom of the Baltic Sea, and conducting rescue operations. But these days, after an exceptionally high number of submarine cables have been damaged, the navy has a new mission—protecting marine infrastructure.
“Here, we see all the ships around us and all the information about them. This, for example, is a friendly object,” says one of the sailors while showing the radar.
Since the beginning of 2025, the crew of this mine-sweeper has participated in NATO operations aimed at protecting the Baltic Sea. Their area of responsibility stretches from the port of Tallinn to the middle of the Gulf of Finland, about two hours of sailing time.
“Since the incident with the cables, the Estonian Navy has assigned three ships—one of them is ours, the Sarkala. What we’re doing here is patrolling the area, monitoring all traffic going west and east, in both directions,” says Meelis Kants, commander of the warship “Sarkala.”
It was in these very waters that the Estlink-2 energy cable connecting Estonia and Finland was damaged in December 2024. Now, it is the task of the Estonian Navy to protect the second cable located on the seabed in the Gulf of Finland.
“If something seems suspicious, we approach the ships and also contact them if necessary,” says Commander Kants.
In recent weeks, more than 10 submarine cables have been damaged in the Baltic Sea. While there is no definitive evidence of sabotage, some sailors suspect that an accidentally dropped anchor may have caught the cables on the seabed.
Estonian military officials say active investigations are underway regarding the possibility of sabotage.
“The cables were broken by anchors being dragged. Civil commercial ships have been sailing and dropped their anchors. The question is—was it done deliberately or was it an accident? Investigations are ongoing, criminal investigations for all these incidents,” says sailor Johan-Elias Seljamaa.
During the patrol, the Estonian Navy—together with the Finnish Navy—organizes small military exercises. For these experienced sailors, this provides additional training, although they are fulfilling their more serious duty of monitoring these vital pipelines that connect Nordic countries with the Baltic states.
