Sweden seizes vessel after damage to Latvian underwater fiber-optic cable in Baltic Sea

The Swedish Public Prosecutor's Office has seized a vessel as part of an investigation into damage to an underwater fiber-optic communication cable connecting Sweden and Latvia, according to a statement on its website released earlier today. A preliminary investigation has been launched, with suspicions pointing to sabotage. The damage to the cable in the Baltic Sea was discovered on Jan. 26.

The prosecutor's office stated that “a number of concrete investigative measures” are being conducted but did not disclose further details. The name of the vessel in question has not been made public. The investigation involves Swedish police, the coast guard, and the country’s armed forces.

The damaged cable, owned by the Latvian State Radio and Television Center (LVRTC), is located within Sweden's exclusive economic zone. LVRTC described the damage as significant, with grounds to suspect external interference. A Latvian Navy patrol ship inspected the vessel Michalis San, which was en route to Russia and had been detected near the cable break. No suspicious findings were reported aboard the ship.

Yesterday’s incident follows a series of suspicious cable disruptions in November and December, which saw damage inflicted on underwater power and communication lines in the Baltic Sea. Authorities in the affected countries suspect sabotage, potentially linked to Russia.

In December, Finnish authorities detained the tanker Eagle S, which is suspected of being part of Russia’s “shadow fleet,” a collection of poorly maintained vessels that help Moscow trade oil at prices above the Western-imposed $60 cap. The tanker is accused of damaging four telecommunications cables — along with the Estlink 2 power cable connecting Finland and Estonia — by dragging its anchor along the seabed. British maritime journal Lloyd’s List, citing an unnamed source directly involved with the vessel, later reported that the Eagle S was equipped with spy equipment capable of monitoring NATO ships and aircraft.

In January, NATO announced the launch of the Baltic Sentry mission to safeguard critical infrastructure in the Baltic Sea. The operation will involve patrols by frigates, maritime patrol aircraft, and unmanned naval drones.