Finnish and Estonian authorities are recording steady activity by Russia’s so-called "shadow fleet" in the Baltic Sea. Vessels with opaque registration and disabled tracking systems continue to traverse key maritime routes, exploiting loopholes in international law and leaving coastal states without effective deterrence mechanisms. This data is confirmed by official statements from the Finnish Ministry of Defence, national agencies, and investigative reports from regional media like Narva News and Yle.

Key Tactics of the Shadow Fleet

According to Finnish observers, at least 15 tankers flying flags from Liberia, Panama, and Cameroon have disabled their transponders near the Russian coast in recent months—a clear sign of attempts to evade sanction controls. The Finnish Ministry of Defence reports that these vessels are now frequently accompanied by Russian Navy ships when passing through the Gulf of Finland, though no direct threat to territorial integrity has been identified so far.

The Commander of the Finnish Coast Guard noted a deliberate trend of turning off Automatic Identification Systems (AIS), resulting in significantly distorted location data. "...(AIS) devices were intentionally disabled, causing position information to be displayed incorrectly... this is directly linked to sanctions evasion," a Coast Guard representative stated.

Infrastructure Sabotage: The Estlink 2 Incident

In December 2024, the Estlink 2 undersea power connection was severely damaged. Finnish authorities linked the incident to the tanker Eagle S, which reportedly dragged its anchor across the seabed for nearly 100 kilometers, damaging five cables.

• Legal Action: Finnish prosecutors charged the crew with aggravated sabotage and interference with communications.

• Court Ruling: In late 2025, a Finnish court dismissed the criminal case, citing a lack of jurisdiction as the damage occurred outside Finnish territorial waters. The court ruled that jurisdiction lies with the vessel’s flag state (Cook Islands) or the crew's home countries.

• Current Status: The Finnish Transport Agency has identified "serious technical deficiencies" in the Eagle S, making its operation illegal until fixed.

Legal Hurdles and International Law

The UN Convention on the Law of the Sea (UNCLOS) remains a primary obstacle for coastal states. Under international law:

• Ships in international waters fall under the jurisdiction of their flag state.

• Coastal nations struggle to legally board or seize vessels unless they are proven "stateless" or "falsely flagged."

• Proving a lack of valid insurance is a complex process that hampers rapid intervention.

Coordinated European Response (2025–2026)

In January 2026, a coalition of 14 countries (including Estonia, Finland, Germany, and the UK) issued a joint letter to the international maritime community. They warned that "shadow fleet" deceptive behavior—such as location spoofing and flag-hopping—endangers maritime safety and environment.

Conclusion: Despite increasing pressure, Russia's "shadow fleet" continues to function in Europe's strategic routes through a mix of technological tricks and legal maneuvers. While Finland and Estonia are leading the charge for a "maritime surveillance hub," the clash between international maritime norms and practical enforcement capabilities keeps the Baltic Sea a "thoroughfare" for these high-risk vessels.