The Black Sea is becoming an increasingly dangerous place for commercial shipping as Russia’s war on Ukraine spills beyond the battlefield. Sofia is turning to the EU and NATO for help strengthening security in the area.

European Commission President Ursula von der Leyen has strongly condemned drone attacks on merchant ships in the Black Sea near Bulgaria’s coast. One of the two vessels came under attack sank on Tuesday.

“The Black Sea has become another front of escalation of the Russian war in Ukraine. This is unacceptable. I strongly condemn the drone attacks on merchant ships near Bulgaria’s coast,” von der Leyen wrote.

She warned that the attacks threaten the lives of crews and security across the Black Sea. “We stand with Bulgaria and thank its rescuers for their swift response. Those responsible should be held accountable,” she added.

Two ships hit, one sinks

Bulgarian Prime Minister Rumen Radev said authorities received a distress call at 01:30 local time on Tuesday from the merchant vessel Chelsea 3, about 18 nautical miles east of the town of Byala.

According to the crew, three aerial drones struck the vessel, which sails under the Maltese flag. The ship is registered in Odesa and belongs to a Ukrainian owner. All 15 crew members, seven Ukrainians and eight Azerbaijanis, were taken to the port of Varna. Five required medical attention.

Bulgarian authorities also received reports of another vessel hit by drones about 17 nautical miles east of Krapets. The ship sank, but rescuers managed to save one crew member. The authorities are searching for others still missing.

Sofia has asked the EU and NATO to support the investigation, which aims to establish where the drones came from. It has also requested help strengthening surveillance of the airspace and waters in the area.

After a phone call with Mr Radev, NATO Secretary General Mark Rutte said the alliance would continue working with its Black Sea allies. He added that NATO stood ready to adjust its military presence in the region as needed.

Bulgaria summons Russian ambassador

Mr Radev said it was not yet possible to identify the party responsible with certainty. “However, as I have already stated, the logic suggests that the outcome benefits the Russian Federation,” he added.

He also summoned Russia’s ambassador to Sofia, Eleonora Mitrofanova. According to Bulgarian media citing official government information, Ms Mitrofanova said she “does not have any information from the Ministry of Defence of the Russian Federation related to the recent attacks on merchant ships in the Black Sea”.

She did not rule out a provocation by a “third party”. Mr Radev told her that there is “no logic for Ukraine to destroy its own ships”.

Ukraine’s Foreign Minister Andrii Sybiha blamed Russia for the attack, saying it “once again demonstrates Moscow’s deliberate disregard for civilian lives and maritime security in the Black Sea”. He urged international partners to increase pressure on Moscow.

“The Black Sea is a lifeline for global food security. Russia is attacking it to weaponise hunger and hold the world hostage,” he wrote.

This is not the first such incident in the area. Last week, drones attacked two cargo ships in Bulgaria’s exclusive economic zone. One sank, and Bulgarian authorities later called off the search for its crew.