Factbox-Timeline of suspected underwater sabotage in Baltic Sea

Jan 2 (Reuters) - The Baltic Sea region is on high alert after a string of power cable, telecom link and gas pipeline outages since Russia invaded Ukraine in 2022, and the NATO military alliance has boosted its presence with frigates, aircraft and naval drones.

Police have found that some incidents were caused by sabotage while others were accidental or remain subject to ongoing proceedings.

DECEMBER 2025: FINLAND-ESTONIA TELECOM CABLE

Finnish police on December 31 seized a cargo vessel en route from Russia to Israel on suspicion of sabotaging an undersea telecoms cable running from Helsinki across the Gulf of Finland to Estonia.

The vessel Fitburg was caught dragging its anchor in the sea and was subsequently directed into Finnish territorial waters, police said.

Investigators said the ship's 14 crew members were from Russia, Georgia, Kazakhstan and Azerbaijan and that two of them had been arrested while two others were banned from travel while an investigation was ongoing.

JANUARY-FEBRUARY 2025: SWEDEN-LATVIA AND FINLAND-GERMANY TELECOM CABLES

An undersea fibre-optic cable connecting Latvia and the Swedish island of Gotland malfunctioned on January 26, prompting an investigation by NATO and police.

Sweden later seized and boarded the Maltese-flagged bulk vessel Vezhen on suspicion that it had caused the damage in an act of gross sabotage.

Bulgarian shipping company Navigation Maritime Bulgare said that Vezhen's anchor had dropped to the seabed in high winds and may have struck the cable, but denied any sabotage.

A Swedish prosecutor later ruled the breach accidental and released the vessel.

The following month, Finnish telecoms operator Cinia said it had detected problems on its C-Lion1 link connecting Finland and Germany, but concluded that the damage might have occurred as early as January 26, the day of the Gotland incident.

DECEMBER 2024: POWER AND INTERNET CABLES

The Estlink 2 undersea power cable connecting Finland and Estonia was cut on December 25 along with four telecoms lines.

Finland seized the Cook Islands-registered Eagle S tanker on suspicion it caused the damage by dragging its anchor, adding that the ship was part of a "shadow fleet" circumventing sanctions on Russian oil.

The Kremlin said the ship's seizure was of little concern to it.

Finnish police later recovered a lost anchor they said was believed to belong to the ship.

In October 2025, a Finnish court dismissed a case against the Eagle S captain and other crew members, ruling prosecutors failed to prove intent and that any negligence must be pursued by the ship's flag state or the crew's home countries.

No charges were brought against the ship's owner, United Arab Emirates-based Caravella LLC FZ, and the vessel was released from custody.

NOVEMBER 2024: BALTIC TELECOM CABLES

Two undersea fibre-optic communications cables located more than 100 nautical miles (about 200 km) apart in the Baltic Sea were severed on November 17 and 18, raising suspicions of sabotage.

Investigators zeroed in on Chinese bulk carrier Yi Peng 3, and a Reuters analysis of MarineTraffic data showed that the ship's coordinates corresponded to the time and place of the breaches.

China allowed representatives from Germany, Sweden, Finland and Denmark on December 21 to board the Yi Peng 3 along with Chinese investigators, after a month-long diplomatic standoff.

A Swedish inquiry found no conclusive evidence to suggest that the ship deliberately dragged its anchor to damage the cables, Sweden's Accident Investigation Authority said in April.

OCTOBER 2023: BALTICCONNECTOR GAS PIPE AND CABLES

A subsea gas pipeline, the Balticconnector, which links Finland and Estonia, was severed by what Finnish investigators determined was Chinese container vessel NewNew Polar Bear dragging its anchor on October 8, 2023.

Estonian police suspected the ship of also damaging telecoms cables connecting Estonia to Finland and Sweden on October 7-8, before hitting the gas pipeline on its way to a port near St Petersburg in Russia.

The ship's captain appeared in court in Hong Kong in a pre-trial hearing last year accused of causing "criminal damage" to the pipeline and cables, according to a Hong Kong charge sheet seen by Reuters.

SEPTEMBER 2022: NORD STREAM BLASTS

Nord Stream 1 and Nord Stream 2, built across the Baltic Sea by Russia's state-controlled Gazprom to pump natural gas to Germany, were damaged in explosions in September 2022.

Some Western officials suggested Russia blew up its own pipelines, an interpretation dismissed by Moscow, which has blamed the United States, Britain and Ukraine for the blasts, which largely cut Russian gas off from the European market.

Those countries denied involvement.

In November 2025, Italy's top court approved the handover to Germany of a Ukrainian man suspected of coordinating the sabotage.

A Polish court last year ruled against handing over a Ukrainian diving instructor sought by German prosecutors.

(Reporting by Anne Kauranen and Essi Lehto in Helsinki, Nerijus Adomaitis and Terje Solsvik in Oslo, Johan Ahlander in Gothenburg, Stine Jacobsen in Copenhagen, Andrius Sytas in Vilnius, Anna Ringstrom and Simon Johnson in Stockholm and Agnieszka Olenska, Elviira Luoma and Jagoda Darlak in Gdansk; editing by Alex Richardson, David Evans and Mark Heinrich)