An undersea fiber optic cable between Latvia and Sweden was damaged on Sunday, likely as a result of external influence, Latvia said, triggering an investigation by local and NATO maritime forces in the Baltic Sea.

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.

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.

A subsea cable connecting Latvia to Sweden’s Gotland island is the latest cable to be damaged in the Baltic Sea. Owned by Latvia’s State Radio and Television Centre (LVRTC), the cable’s Ventspils–Gotland segment was damaged early on January 26, at depths of 100m.

Baltic Sea as part of a mission to protect undersea cables and pipelines. As authorities investigate the fourth Baltic Sea cable-cutting incident in recent months, European leaders have expressed concern about the frequency of attacks involving civilian vessels and critical civilian infrastructure.

Over the past 15 months, 11 undersea cables in the Baltic Sea have been damaged, creating serious concerns for the security of Europe’s communication and energy networks. These cables are essential for the smooth operation of countries bordering the Baltic,