A drone strike sank a cargo ship off Romania’s Black Sea coast on Friday, killing one sailor and leaving three missing, as a spate of attacks on commercial vessels raises concerns over the safety of shipping in the region.According to Reuters, the Comoros-flagged cargo ship Khoryv, carrying 13 Ukrainian and Azerbaijani sailors, sent a distress signal about 13 nautical miles from the Romanian port of Constanta. Nine crew members were rescued, while three remained missing.Romanian President Nicusor Dan blamed Russia for the incident, describing it as part of Moscow’s escalating military campaign. “It is part of Russia’s escalation process in its war in Ukraine,” Dan said, according to Reuters.The sinking comes amid a series of attacks on commercial vessels near Romania and neighbouring Bulgaria, both Nato members. At least seven cargo ships were reportedly hit in the area over the preceding two weeks, heightening concerns about the growing threat to civilian shipping in the western Black Sea.The attacks also threaten a key trade route for Ukraine. Vessels targeted in recent incidents were near or heading towards the Sulina Canal, which connects the Danube River to the Black Sea and serves as an important corridor for Ukrainian grain and food exports.There was no immediate response from Moscow to Romania’s accusation over the latest sinking, Reuters reported. Russia has previously denied responsibility for similar incidents, with its embassy in Romania saying in an earlier case that Moscow was not involved in drone attacks on vessels near the Romanian coast.NATO steps up Black Sea securityNato has said it will deploy additional maritime patrol aircraft, radar systems and drones to the Black Sea amid mounting concerns over attacks on commercial vessels near Romania and Bulgaria.Romania’s defence council has also pledged to accelerate the development of maritime surveillance and counter-drone capabilities, while strengthening coordination with Nato allies Bulgaria and Turkey.The Black Sea is a critical trade and military corridor linking Eastern Europe to the Mediterranean through the Turkish Straits. It serves as a major route for Russian and Ukrainian grain, oil and other commodity exports, making maritime security essential for global supply chains.The region also borders three Nato members, Romania, Bulgaria and Turkey, raising the strategic stakes as Russia-Ukraine war-related attacks increasingly threaten commercial shipping and regional stability.