Romania said on Wednesday that it is probing a possible fresh drone attack on a tanker off its Black Sea coast.
Suspected Russian drones have hit several ships off Romania and neighbouring Bulgaria since last week in the latest spillover from the Ukraine war in the Black Sea.
Romanian rescuers rushed to help the Comoros Islands-flagged Yara J overnight off Sulina near the border with Ukraine, a statement said.
Defence Minister Radu Miruta said the ship's crew managed to douse a fire themselves.
"Whether it was struck by a drone or not, an investigation is currently underway," he told the Digi24 television channel.
"This is a matter of significant gravity, given that such incidents are occurring in Romanian territorial waters," he said.
The VesselFinder tracking website identified the Yara J as a chemical/oil products tanker.
Miruta said the vessel, docked off Sulina for "several days", was empty.
The defence ministry in a press release earlier said it had scrambled two F-18 jets after "detecting a group of air targets off the Black Sea".
Black Sea strikes
Meanwhile on Wednesday, Bulgaria said Russia was likely behind drone attacks that struck four ships in the Black Sea in the past week, sinking two, but there was no way of proving Moscow's culpability.
Rescuers are still searching for 11 crew members missing after drone strikes on Tuesday sank two ships in Bulgaria's exclusive economic zone and adjacent waters, while five other crew members were rescued.
One of the ships is registered to Guinea-Bissau but the other one, the Chelsea-3, is Ukrainian-owned, registered in Odesa and sails under the flag of Malta, a European Union member.
“There is no logic in Ukraine attacking its own ships and crews, given that the outcome of all these attacks favours Russia and indeed, the logic points in that direction. The problem is that we cannot prove it,” Bulgarian Prime Minister Rumen Radev told Parliament.
On Tuesday, Radev summoned the Russian ambassador to Sofia, who said she does not have any information from the Russian defence ministry but she did not rule out the possibility that “these attacks represent a provocation by a third party.”
The Guinea-Bissau-flagged cargo ship Dignity sank on Tuesday after it was hit by a military strike. Four sailors, three Syrian nationals and one Egyptian, were rescued and arrived in the port of Varna, district Gov. Mario Smarkov said.
“All four appeared to be in relatively good condition and had sustained no injuries,” he said. A fifth sailor is expected to arrive later on Wednesday.
Smarkov said the search for the 11 missing crew members continues.
Bulgaria has requested international assistance for the investigation into attacks on commercial vessels, as well as NATO support to strengthen surveillance and control systems and response capabilities against drone attacks.
Black Sea security
The incidents have renewed scrutiny of Europe's ability to protect shipping and critical infrastructure in the Black Sea, more than a year after the EU launched a strategy to strengthen security in the region.
When the Black Sea Security Strategy was unveiled in May 2025, EU foreign policy chief Kaja Kallas warned that the region was bearing the spillover effects of Russia's full-scale invasion of Ukraine.
"The Black Sea region is the prime target for hybrid actions. The European Union aims to boost cooperation to combat cyberattacks, disinformation, and other hostile actions," she said.
“Recurring airspace violations and attacks on ports and shipping lanes highlight this reality."
The policy was aimed at ensuring the security of this maritime corridor, as well as protecting critical infrastructure and assets, such as offshore installations and subsea cables.
It also promised the development of a Black Sea Maritime Security Hub aimed at coordinating support and boosting coast-guard cooperation, among other activities.
The hub would also analyse seabed sensor data and alert allies to potential dangers and incoming threats.
Additional sources • AP, AFP