Romania is investigating whether a tanker was hit by a drone off its Black Sea coast, while Bulgaria searches for missing sailors after separate attacks damaged or sank commercial vessels. The incidents have intensified concern over maritime security and the protection of critical infrastructure near the war in Ukraine.
The developments form part of a wider pattern of reported drone strikes involving shipping in and around the Black Sea. They have also renewed questions about whether European countries have sufficient systems to detect, attribute and respond to threats against commercial vessels.
Romania probes incident involving the Yara J
Romanian authorities said rescuers responded overnight to the Comoros-flagged Yara J near Sulina, close to Romania’s border with Ukraine. The vessel was identified by tracking data as a chemical and oil-products tanker and had reportedly been waiting offshore for several days.
Romania’s Defence Minister Radu Miruta said the crew extinguished a fire themselves. He stressed that investigators had not yet established whether the ship was struck by a drone.
Romania’s defence ministry said two F-18 fighter jets were scrambled after air targets were detected over the Black Sea. The tanker was reported to be empty at the time of the incident, reducing the immediate risk of a cargo-related emergency, although any attack on a commercial vessel in territorial waters raises serious safety and security concerns.
Why territorial waters matter
Romania’s territorial sea extends up to 12 nautical miles from its coast under international maritime law. An incident in those waters places direct responsibility on Romanian authorities for emergency response, investigation and coordination with relevant international partners.
The case is not yet a confirmed attribution of responsibility. Authorities are examining the available evidence, including damage to the vessel, flight activity and information from maritime and military surveillance systems.
Bulgaria reports attacks on ships in nearby waters
Bulgaria said four ships had been affected by drone attacks during the previous week. Two vessels reportedly sank in Bulgaria’s exclusive economic zone and adjacent waters, while several crew members were rescued and others remained missing.
One of the vessels was the Guinea-Bissau-flagged Dignity. Bulgarian authorities said four sailors—three Syrian nationals and one Egyptian—were rescued and taken to Varna. A further sailor was expected to arrive later, while search operations continued for 11 missing crew members.
The other sunken vessel, the Chelsea-3, was described as Ukrainian-owned, registered in Odesa and operating under the Maltese flag. Malta is an EU member state, giving the incident an additional connection to European maritime and shipping interests.
Bulgarian Prime Minister Rumen Radev told Parliament that Russia was considered a likely source of the attacks, but acknowledged that there was no proof establishing Moscow’s responsibility. The Russian ambassador in Sofia said she had no information from Russia’s defence ministry and suggested the incidents could have been a provocation by a third party.
Requests for international and NATO assistance
Bulgaria has asked for international assistance with the investigation and requested NATO support to improve surveillance, control systems and response capabilities against drone attacks.
The requests reflect the difficulty of protecting commercial shipping in a busy maritime area where military operations, civilian traffic and critical infrastructure overlap. Commercial vessels may also operate under different flags, have owners in different countries and carry multinational crews, complicating both emergency response and legal investigations.
Key challenges include:
- Detecting low-flying drones over a large maritime area.
- Distinguishing military activity from civilian air and sea traffic.
- Sharing surveillance data quickly between neighbouring countries.
- Rescuing crews after fires, explosions or sinkings.
- Establishing responsibility before making a formal attribution.
EU Black Sea strategy faces renewed scrutiny
The incidents have drawn attention to the European Union’s Black Sea Security Strategy, unveiled in May 2025. The strategy was designed to strengthen cooperation in a region affected by Russia’s full-scale invasion of Ukraine and increasing risks to ports, shipping routes and infrastructure.
The EU policy addresses several areas, including:
- Protection of maritime routes and critical infrastructure.
- Cooperation against cyberattacks and disinformation.
- Improved coordination among coast guards and other authorities.
- Monitoring of offshore installations and subsea cables.
- Development of a Black Sea Maritime Security Hub.
The proposed hub is intended to support information-sharing, analyse seabed sensor data and help alert partners to possible threats. The latest incidents have raised questions about how quickly these arrangements can provide practical protection for commercial shipping.
What happens next?
Romanian and Bulgarian authorities are expected to continue collecting evidence, interviewing survivors and examining vessel damage. International cooperation may be necessary because the affected ships are linked to several flags, owners and crew nationalities.
Any conclusion about responsibility will depend on verified military, maritime and forensic evidence. Until that process is complete, claims about who carried out the attacks remain allegations rather than established findings.
For Ireland, the incidents underline the wider importance of European maritime security, even though the reported attacks occurred in the Black Sea. Irish-linked shipping, energy infrastructure and subsea communications systems are part of a broader European network exposed to risks from drones, sabotage and other hybrid threats. The events may therefore influence discussions about surveillance, NATO cooperation and EU protection of critical infrastructure.
Conclusion
Romania’s investigation into the possible drone strike on the Yara J remains open, while Bulgaria continues rescue and investigative operations after attacks on commercial vessels. No definitive responsibility has been established. The immediate priority is to protect crews and shipping, but the incidents also test whether Europe’s existing Black Sea security arrangements can deliver faster detection, stronger coordination and credible protection for vital maritime infrastructure.
