Two telecommunications cables running through the Baltic Sea were damaged in what Germany called an act of 'sabotage.'

In the past two days, two undersea telecommunication cables connecting Finland with Germany and Lithuania with Sweden have failed. The causes of these malfunctions are unknown.

The C-Lion1 cable between Finland and Germany was severed in the Baltic Sea, its operator said, after damage was reported to another cable linking Lithuania and Sweden.

European officials are looking toward Russia after two submarine internet cables in the Baltic Sea were suddenly disrupted in an apparent sabotage operation, just weeks after the United States warned that Moscow was likely to target critical undersea infrastructure.

According to the New York Times, Boris Pistorius, Germany’s defense minister, believes that undersea cables connecting Finland and Germany that were severed on Monday were not damaged by accident, the New York Times reports.

German officials said on Tuesday they believe the damage to two underwater fiber-optic cables in the Baltic Sea was an act of sabotage, but they could not speculate beyond that.

German Defense Minister Boris Pistorius said damage to two undersea data cables in the Baltic Sea has to be investigated as an act of sabotage, pointing to Russia as posing a hybrid and military threat to the European Union.