The crew of the Bulgarian ferry Dioscuria first learned of an attack on a cargo ship in their country’s exclusive economic zone in the Black Sea in the early hours of 6 October when they heard a distant explosion 70 miles off the coastal town of Byala. The Turkish-owned Alfa Watan, bound for the Romanian port of Sulina, had been struck by suspected Russian air and naval drones. When the Dioscuria arrived at the scene, it found an overturned lifeboat and lifejackets in the water. There was no sign, however, of the Alfa Watan’s crew of 10.
Map showing the location of ships attacked in the Black Sea’s EU waters in October.
Six days later, drones struck another ship off the coast of Bulgaria, the HS Dignity. Eleven crew members died. By Thursday, the attacks had reached Romania’s airspace and territorial waters. Two chemical tankers, the Wine Trader and the Yara J, were attacked and left burning. Seven more sailors were missing.
Four of the rescued sailors from the HS Dignity on a Bulgarian navy rescue tug, which transported them to the port of Varna on Tuesday. Photograph: moreto.net/AP
Crew members from the Able, which was damaged in a drone attack, disembark from a Bulgarian border police vessel in Varna after a rescue operation. Photograph: Petko Momchilov/Reuters
The attacks on six ships in 10 days โ the Able and the Chelsea-3 were also hit โ marked a dramatic escalation in a maritime conflict that is pressing on Nato’s borders. While global attention has focused on the risks for sailors travelling through the Strait of Hormuz, in recent months it is the Black Sea that has emerged as the more dangerous passage, with more sailors lost in a week and a half than US service members killed in the entire Iran war.
The Alfa Watan, which sank after a drone attack, sails in Istanbul, Turkey, the day before the incident. Photograph: Yoruk Isik/Reuters
The maritime insurer and risk analyst Ambrey has warned that there is no end in sight to the threats to Black Sea cargo shipping, including grain and oil, and that insurance prices for passage through the waters have rocketed. Tomas Alexa, a senior analyst at Ambrey, has noted a sharp increase in the pace of attacks beginning in July. Russian forces are estimated to be responsible for 80% of them. The recent loss of life, he suggests, has been worsened by “double tap” attacks involving aerial and surface drones, the latter often carrying up to half a tonne of explosive payloads. Smaller vessels that mainly use the Danube canal system have sunk rapidly.
“While attacks against merchant vessels in the Black Sea are not new, we are seeing an escalation both in terms of the number of attacks and in the geographical scope,” Alexa said. The profile of vessels being attacked โ that is, ships trading with Ukraine โ had not changed, he added. “The Russian intent is clear, which is to degrade the export of Ukrainian grain and agricultural products.”
The Comoros-flagged chemical and oil tanker Yara J transits the Bosphorus strait in Istanbul, Turkey, last month. Photograph: Yoruk Isik/Reuters
The result has been a steep fall in the number of vessels visiting Ukraine. Insurance rates have soared, and seafarers and operators have become increasingly reluctant to operate in the Black Sea basin, even on ships unconnected with Ukrainian cargoes. The vast majority of the more than 60 seafarer fatalities in the Black Sea since Russia’s full-scale invasion of Ukraine in February 2022 have occurred in the past year. In September the Joint War Committee, representing the London insurance market, moved to extend the high-risk areas of the Black Sea to include the whole of the basin, excluding the territorial waters of Turkey, Romania, Bulgaria and Georgia.
The threat is not confined to the Black Sea itself. Attacks on Ukraine’s Black Sea ports have also increased sharply in the past year. A number of factors are driving the expansion and escalation of the conflict towards the shores of Nato countries, say experts. Russia has respondRussia has expanded its attacks on Ukraine’s shadow fleet of oil tankers by increasingly targeting Ukrainian agricultural cargoes, a key part of Kyiv’s economy. As ships moved further from the coastlines in search of safer passage, the threat changed from naval mines to drones with ever longer ranges. Ursula von der Leyen, the European Commission president, said after the sinking of the Alfa Watan: “Commercial ships โ and innocent crews โ are being targeted, with lives already lost at sea.”
Demonstrators gathered in Sofia, Bulgaria, on Thursday to demand answers about recent Black Sea maritime attacks. In a statement at the Organization for Security and Co-operation in Europe, Col Joby Rimmer, a senior British military adviser, said: “Attacks that fail to distinguish between military objectives and civilian vessels, or that are expected to cause excessive incidental harm to civilians and civilian vessels in relation to the anticipated military advantage, may violate international humanitarian law and the UN convention on the law of the sea.
“Each attack raises the risk to crews of every nationality, drives up insurance costs and restricts the flow of food to those who depend on it. The UK is deeply concerned by the far-reaching consequences of successive crises across the global maritime domain. Stable and secure sea lanes are a global common good from which we all benefit.”
Operators have warned of the wider impact on trade in the Black Sea, including from Bulgarian ports. In a recent interview on Bulgarian television, shipping agency owner Todor Georgiev warned the Black Sea was in danger of becoming a “dead zone”.
A vessel hit by a drone in the Black Sea this week. “Whenever the Russians are caught having struck a ship with one of their drones, they claim the vessel was carrying weapons,” he said. “Weapons are not being transported to Ukraine via the Black Sea.”
Rumen Radev, Bulgaria’s prime minister, has described the attacks near his country’s territorial waters as “absolutely unacceptable”. Bulgarian officials are calling for the EU and Nato to support efforts to enhance security, while working with Turkey and Romania on increased regional security. Although they have refused to blame Russia, officials have said there is “no logic” for Ukraine to attack its own shipments.
A cargo ship in the Black Sea on Thursday. “We do not have clear and conclusive evidence to attribute responsibility to either side,” said Radev. “However, as I have already stated, the logic suggests that the outcome benefits the Russian Federation.”
As Russian strikes on shipping move ever closer to the borders of Nato members, they pose mounting security challenges to the mutual defence organisation, which is already confronting Moscow’s growing hybrid warfare across Europe. There is speculation that the affected Nato countries may be forced to invoke article 4 of the organisation’s treaty, a step below the article 5 invocation of mutual self-defence. It has been triggered twice already in connection with the Ukraine war โ in the immediate aftermath of Russia’s invasion of Ukraine in 2022 and by Poland in 2025 after Russian drones violated Warsaw’s airspace โ and calls for formal crisis discussions on a security threat.
On Thursday Mark Rutte, Nato’s secretary general, met Radev and Nicuศor Dan, Romania’s president, to discuss security in the Black Sea. Rutte said: “Nato will continue to work closely with our allies in the Black Sea, adjusting our deterrence and”defence posture as needed.” Another consequence of the escalating attacks is the renewed danger of a global food crisis. Ukraine and Russia are major grain exporters, as is Romania. View image in fullscreen Diners at a restaurant overlooking the harbour in Varna. Photograph: Nikolay Doychinov/AFP/Getty Images “We see the Black Sea as a global food artery,” said Oana Toiu, the Romanian foreign minister, at a security conference in Warsaw last week. “Unfortunately, it is currently the deadliest sea in terms of sailor casualties in recent months. That means we need to invest more in deterrence and defence.” Damien Chevallier, director of maritime safety at the UN’s International Maritime Organization, warned last month about the long-term impact on shipping from attacks linked to the conflicts in Ukraine and the Middle East. “With rising casualties across the Black Sea, Red Sea and Strait of Hormuz, being a seafarer has become a genuinely dangerous profession,” he said. “Seafarers are not trained to deal with threats from actions linked to wider security issues or geopolitical situations. “What makes this moment truly unprecedented is not just the number of incidents, but the pattern behind them. Shipping has become a deliberate instrument of geopolitical leverage.”
Frequently Asked Questions
Heres a set of FAQs on this topic
1 Whats happening with drone attacks on ships in the Black Sea
Both Ukraine and Russia have been using sea drones and aerial drones to attack ships and port facilities Ukraine has hit Russian warships and oil terminals Russia has struck Ukrainian ports and grain facilities
2 What is a sea drone
A small remotecontrolled or selfguided boat that carries explosives or cameras Theyre cheap compared to warships and can be launched in swarms
3 Why does this matter for NATO
The Black Sea borders three NATO members Romania Bulgaria and Turkey Drone strikes drifting mines and disrupted shipping near these coasts raise the risk of accidents or escalation involving NATO countries
4 Which NATO countries are most exposed
Romania and Bulgaria because of their proximity to Ukrainian and Russian strikes and to shipping lanes Turkey controls the straits into the Black Sea and is closely involved
5 How close are the attacks to NATO territory
Some strikes have hit targets near Romanias border and debris from drones has landed on Romanian soil Romania has scrambled fighter jets in response
6 Could a drone accidentally hit a NATO ship or port
Thats the core worry Drones can go off course be jammed or misidentify targets An accidental strike on NATO territory could trigger Article 5 debates
7 What is Article 5
NATOs collective defense clause an attack on one member is treated as an attack on all It has only been invoked once after 911
8 Has NATO responded
Yes NATO members have boosted air policing surveillance and naval patrols in the region and Romania has deployed additional forces and radar systems
9 Why is the Black Sea so important
Its a major route for grain oil and other trade Disruption raises food prices and insurance costs and threatens global shipping
10 Are commercial ships at risk
Yes Several civilian vessels have been damaged and insurers have raised premiums for ships entering the region Shipping companies have become more cautious
11 What are drifting mines
Naval mines that break loose from their moorings and float unpredictably Turkey Romania and Bulgaria have a joint task force to clear them
