Black Sea Drone Strikes: Five Merchant Ships Hit Off NATO Coasts

Varna, Bulgaria, October 13, 2026 — Drones struck two more merchant ships off Bulgaria’s Black Sea coast overnight, sinking one and leaving 11 sailors missing. It was the third round of attacks on civilian cargo vessels near NATO coastlines in nine days, and the closest yet to Bulgaria’s shore.

Prime Minister Rumen Radev said the Maltese-flagged, Ukrainian-owned Chelsea 3 was “hit by three aerial drones” after a distress signal at about 1:30 a.m. local time. A Bulgarian Border Police team rescued all 15 crew members, seven Ukrainians and eight Azerbaijanis, and five were treated for minor injuries, according to Radev. Bulgarian National Radio reported that the 136-meter ship had been sailing from Giresun in Türkiye to Giurgiulești, with cargo declared for Moldova, and was later left listing and unmanned.

While Radev’s emergency security council was meeting, officials learned of a second strike farther north. That ship sank off the village of Krapets. Five crew members were rescued, and 11 were still missing on Tuesday, regional officials said. Early Bulgarian reports named the vessel Azov Concord; President Iliana Iotova’s office later identified it as HS Dignity, flying the flag of Guinea-Bissau.

Who Bulgaria blames, and how carefully

Sofia has not formally attributed the attacks. “We do not have clear evidence to accuse any of the parties,” Radev said. “But logic indicates that the result is in favour of the Russian Federation.” He summoned Russian Ambassador Eleonora Mitrofanova, notified Bulgaria’s permanent representatives to NATO and the EU, and asked allies for help to establish “which country the drones” came from.

Iotova’s statement went further on the stakes than on blame. She called the attacks “a blatant violation of international humanitarian and maritime law” and said the escalation “is turning the Black Sea into a war zone.” She also urged quick action on recommendations from the national security council she convened on October 7.

Others named Moscow directly. European Commission President Ursula von der Leyen called the strikes “another front of escalation of the Russian war in Ukraine,” and Ukrainian Foreign Minister Andrii Sybiha accused Russia of “deliberate disregard for civilian lives and maritime security.” After the October 6 strikes, Russia’s embassy in Sofia told Reuters that the ships hit then were not on the Defence Ministry’s target list. The sources reviewed for this article had reported no Russian response to Tuesday’s attacks by publication time.

Timeline: five ships in nine days

The pattern since October 5, compiled from Romanian and Bulgarian official accounts as reported by the outlets cited:

Distances differ slightly between the prime minister’s and the president’s statements, so the table gives the range officials cited. On October 5, Romanian authorities named no suspect; Ukrainian President Volodymyr Zelensky blamed “two Russian drones.” The Euronews account of that sinking reported the ship was attacked about nine nautical miles from Romania’s Pescăruș offshore platform.

Why the attacks are moving toward NATO shores

The geography explains much of the risk. Reuters, in a report carried by CNA, noted that Russian strikes on Ukraine’s main Black Sea ports have pushed Ukrainian trade toward Danube river ports and routes that hug the Bulgarian and Romanian coasts. Chelsea 3, sailing toward Moldova, and the Danube-bound traffic it represents now run along the edge of two NATO members’ waters. The maritime risk firm Ambrey said last month that at least 45 merchant vessels had been attacked over 12 months in Black Sea areas not previously listed as high risk, according to Euronews.

NATO Secretary General Mark Rutte, after a call with Radev, said the alliance had “already strengthened our posture along the eastern flank” and would keep “adjusting our deterrence and defence posture as needed.” The statement did not mention escorts or air defense over commercial shipping lanes.

Analysis: a shrinking buffer and a legal gray zone

Peter’s World analysis based on the sources cited above.

The most important change between the two Bulgarian incidents is distance. A week ago the ships were hit about 70 miles out; on Tuesday they were hit 15 to 18 nautical miles from the beach. Under the UN Convention on the Law of the Sea, a coastal state’s sovereign territorial sea ends at 12 nautical miles, while its contiguous zone, which Iotova named in her statement, may extend to 24. Tuesday’s strikes therefore landed just outside Bulgarian sovereign waters but inside the band where Sofia exercises limited control. An attack there does not, on the facts released so far, amount to an armed attack on Bulgarian territory. It does put drones within a few miles of the line where that question would change.

That gray zone favors whoever is launching the drones. Without recovered debris or tracking data that Sofia is willing to publish, Bulgaria cannot name a culprit, and Radev’s “logic indicates” formula shows a government trying to signal suspicion while keeping diplomatic room. Requests for allied surveillance help are the practical test: if NATO or EU partners share sensor data that fixes the drones’ origin, the political debate shifts from risk management to attribution and response.

For shipping, the cost is rising either way. Crews on small general-cargo ships, one of them built in 1976, are carrying the risk on the Danube corridor; the sailors hit this month came from Syria, Egypt, Ukraine and Azerbaijan, among other countries. Watch for insurer war-risk changes, any convoy or escort proposal from Bulgaria, Romania and Türkiye, and whether the EU’s planned Black Sea maritime security hub moves from strategy to operations.

Sources

• Bulgarian Presidency: President Iotova statement on attacks on merchant ships in the Black Sea
• BNR Radio Bulgaria: Two more commercial ships hit near Bulgarian waters
• The Sofia Globe: New drone attacks on ships in Bulgaria’s Black Sea EEZ, one sunk
• Euronews: At least 11 missing after two ships struck off Bulgaria
• The Maritime Executive: Bulgaria suspends search for missing crew as Russia denies attack

Related coverage

• Russia–Ukraine War Update — October 13, 2026
• Special Report: Russian Hybrid Attacks, the Ukraine War and NATO
• NATO’s Rutte Vows Cheaper Counter-Drone Defenses for Eastern Flank