The damage of two undersea internet cables in the Baltic sea must be seen as an act of sabotage, German defence minister Boris Pistorius has said.
A pair of fibre-optic communications cables were severed on Sunday and Monday, in an incident which “immediately raises suspicions of intentional damage”, Finland and Germany said in a joint statement.
A 745-mile (1,200 kilometre) cable linking Helsinki to the German port of Rostock stopped working at 2am on Monday, according to Finnish state-controlled cyber security and telecoms company Cinia.
Another cable linking Lithuania and Sweden’s Gotland Island went out of service at 8am on Monday, according to a Lithuanian communications firm.
A series of incidents involving Baltic pipelines have heightened fears of sabotage since Russia's invasion of Ukraine.
Before a meeting with EU defence ministers in Brussels, Mr Pistorius said: "No one believes that these cables were cut accidentally. I also don’t want to believe in versions that these were anchors that accidentally caused damage over these cables.
"Therefore we have to state, without knowing specifically who it came from, that it is a ‘hybrid’ action. And we also have to assume, without knowing it yet, that it is sabotage."
In the joint statement, Finland and Germany said they were “deeply concerned”, adding that Europe’s security is threatened by Russia’s war in Ukraine and “hybrid warfare by malicious actors”.
"Safeguarding our shared critical infrastructure is vital to our security and the resilience of our societies," it added.
The Lithuanian navy has now increased its monitoring of its waters in response to the damage. Swedish company Arelion, which owns Lithuanian company Telia Lietuva, revealed the cable is fully out of action.
Carl-Oskar Bohlin, Sweden’s minister of civil defence, told Swedish public broadcaster SVT: "It is absolutely central that it is clarified why we currently have two cables in the Baltic Sea that are not working.”
The Finland-Germany pipeline could take 15 days to repair, Cinia’s chief executive Ari-Jussi Knaapila told reporters at a news conference.
The cable connecting Germany and Finland follows part of the route of the Nord Stream 1 and 2 gas pipelines between Russia and Germany, which were knocked out by a series of underwater explosions in September 2022. German prosecutors are still investigating the explosion, which has led to suggestions that Ukraine or Russia might have been behind the blasts.
In October, the head of MI5 said Russia's intelligence agency has been on a mission to generate "sustained mayhem on British and European streets".