Sweden is investigating damage to a data cable linked to Latvia, the latest breach in the Baltic Sea region where European authorities are on high alert.

Swedish authorities boarded a vessel suspected of being involved in an earlier underwater sabotage of cables in the Baltic Sea on Monday.

After a fiber optic cable was damaged near Sweden, Latvia sent a patrol boat to inspect a suspicious vessel in the Baltic Sea. Sweden later said it seized a vessel believed to have carried out the sabotage.

Swedish authorities have seized a ship suspected of damaging a data cable running under the Baltic Sea to Latvia. The Vezhen - a Maltese-flagged ship - is now anchored outside the Swedish port of Karlskrona.

The Nordic country has opened an investigation into the damage, just weeks after NATO stepped up its military presence in the area following a series of similar incidents.

Hundreds of Swedish troops arrived in Latvia on Saturday to join a Canadian-led multinational brigade along NATO's eastern flank, a mission Sweden is calling its most significant operation so far as a member of the Western defense alliance.

Latvia said it had dispatched a warship on Sunday after damage to a fibre optic cable to Sweden that may have been "due to external factors".

A subsea data cable between Latvia and Sweden was damaged early Sunday, sparking a criminal investigation, a third such incident in the Baltic Sea in the past three months.

As tensions rise, NATO has launched Baltic Sentry 2025 to enhance security and resilience. European Commission President Ursula von der Leyen has emphasized the need for greater coordination in protecting critical infrastructure from sabotage.

The undersea cable is based in the Baltic Sea, and may have been deliberately damaged on Sunday, according to officials in Sweden.

An undersea fibre optic cable between Latvia and Sweden was damaged on Sunday morning, probably as a result of “external influence”, LSM, the Latvian public broadcaster, reported, citing the cable operator.