Constanța port drone blast prompts Ukrainian‑Romanian naval coordination

Ukraine’s Defence Ministry answered 14 questions from Romania’s Defence Ministry about the explosion of a Ukrainian Sargan‑3000 unmanned surface vehicle (USV) in Constanța port on 5 June. The incident followed the loss of contact on 4 June with four USVs near Sevastopol, about 250 km from the Romanian coast, as they moved eastward in the Black Sea.

On 5 June at 09:54 the Ukrainian Navy warned Romanian forces of an imminent self‑destruct sequence that it could not cancel due to lost communications. The drone entered Constanța’s internal waters, travelled roughly 6.5 km and detonated half an hour after the warning, allowing evacuation of personnel with no casualties. Additional explosions were recorded at 11:00 and 13:00 in the open sea. Romanian authorities mobilised coast guard, naval EOD teams and air reconnaissance, issued navigational alerts and informed NATO’s Maritime Command. Romania requested a permanent technical communication channel and programming of drones to self‑destruct at a safe distance from its coast. Ukraine attributed the isolated incident to probable Russian electronic‑warfare interference.