Drones struck two commercial ships in the Black Sea approximately 20 miles off Bulgaria's coastline early Tuesday, sinking one vessel and prompting emergency search-and-rescue operations by maritime border authorities. According to Bulgarian Prime Minister Rumen Radev, one of the targeted vessels—the Maltese-flagged, Ukrainian-owned bulk carrier Chelsea 3—sustained direct hull and deck hits from three aerial drones, forcing the evacuation of its 15 crew members, comprised of seven Ukrainian and eight Azerbaijani nationals. A second commercial vessel was sunk off the coastal village of Krapets, triggering a frantic multinational search for missing mariners after only a single survivor from that vessel was initially pulled from the water.

Following an emergency session of Bulgaria's Security Council, Prime Minister Radev condemned the strikes as 'absolutely unacceptable' and confirmed that Sofia had initiated high-level consultations with NATO Secretary-General Mark Rutte and European Commission leadership. While forensic identification of the drone wreckage remains underway, Radev noted that the strategic objective directly served Moscow's broader operational disruption in the corridor. Ukrainian Foreign Minister Andrii Sybiha explicitly attributed the strikes to Russia, denouncing them as a deliberate escalation targeting civilian maritime infrastructure, while European Commission President Ursula von der Leyen issued a scathing rebuke, warning that the Black Sea has become an increasingly volatile operational theater threatening international freedom of navigation.

The strikes mark a sharp and dangerous geographic escalation of Black Sea hostilities into the maritime economic zone of a NATO member state, threatening to sever commercial maritime trade routes that handle crucial agricultural and raw material exports. The assault raises immediate diplomatic stakes for the western alliance, which has pledged to protect sovereign waters while seeking to avoid direct kinetic clashes. With marine insurance premiums for Black Sea shipping already surging and additional allied air and naval surveillance expected in the western corridor, Sofia and Brussels are preparing formal diplomatic protests while evaluating calls for enhanced naval escort protocols along critical civilian shipping routes.