AFP reported that Finnish telecommunications operator Cinia discovered "an interruption" on the C-Lion 1 cable connecting Finland with Germany. Although the issue does not affect data flows, the cause is still under investigation.
The cable was previously suspected of being cut in November.
The latest incident has raised concerns about sabotage targeting critical infrastructure in the Baltic Sea, amid escalating tensions between the West and Russia over the conflict in Ukraine.
A spokesperson for Swedish police, Mathias Rutegard, confirmed that he is investigating the possibility of "destroying" after receiving reports of a damaged cable system in eastern Gotland.
"We have opened a preliminary investigation into the possibility of sabotage of the underground cable in the Swedish economic zone," said Rutegard.
Currently, no suspects have been identified.
The Swedish Coast Guard summoned a ship to the scene to assist in the investigation.
Swedish Prime Minister Ulf Kristersson said in a post on X that the government is closely monitoring the situation.
"We attach great importance to any reports of possible damage to infrastructure in the Baltic Sea. As I said before, they must be considered in the context of a serious security situation," Prime Minister Kristersson wrote.
Faced with increasing threats, on February 21, the European Commission (EC) announced that it would tighten protection requirements for underground cables, prioritize funding for the deployment of advanced cable systems, and enhance emergency repair capabilities.
Reuters said the EU has also pledged to strengthen sanctions against "hostile actors" and ships of Russia's "shadow fleet" - ships suspected of evading sanctions.
The EU will take measures to prevent, detect, and respond to the threat to underground infrastructure. Although a new funding package has not been announced, Brussels will allocate hundreds of millions of euros to the EU budget to invest in this.
EC plans to develop a monitoring system combined with data, and launch a program for drones and unmanned aerial vehicles to monitor the Baltic Sea.
NATO is also deploying destroyers, patrol aircraft and autonomous flight equipment to protect the gateway to Europe from anonymous attacks.
