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 have seized a ship over the “aggravated sabotage” of an undersea fibre-optic cable linking Latvia with a strategically important island in Sweden.

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.

The Arelion submarine cable, which connects the Swedish island of Gotland to Lithuania, and the C-Lion 1 submarine communications cable that runs between Finland's capital Helsinki and the German city of Rostock were also damaged in mid-November near Sweden's territorial waters.

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.

Sweden detained a vessel suspected of damaging a subsea data cable connecting it with Latvia, the third such incident in the Baltic Sea in the past three months.

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.

Authorities suspect that the cable linking Latvia and Sweden was damaged by an anchor being dragged across the seabed. Read more at straitstimes.com.

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".