Bulgarian minister refers to Russia-Ukraine war as hybrid and says he is unsure whose drones struck vessels

What Happened

On 6 October, drones attacked two merchant vessels in Bulgaria's exclusive economic zone in the Black Sea. Bulgarian Prime Minister Rumen Radev reported that one of the vessels had sunk and the crew members are being considered missing. Bulgarian Defence Minister Dimitar Stoyanov said on bTV, as reported by European Pravda citing BGNES, that it was not yet possible to say whether the drones were Ukrainian or Russian. He described the attack as targeted, not accidental, and said Bulgaria may have become part of what he called the "hybrid war between Ukraine and Russia." Stoyanov said drone debris must be found or one of the parties must claim responsibility; because neither has happened, Bulgarian authorities cannot confirm the origin but believe sea drones were used. President Volodymyr Zelenskyy claimed in the evening that the Ukrainian Navy had contacted its Bulgarian counterparts regarding the attack on two civilian vessels in Bulgarian waters, and that Russia carried out the attack.

Key Actors

Why It Matters

The incident occurred in Bulgaria's exclusive economic zone, bringing maritime spillover of the Russia-Ukraine war into the waters of a NATO and EU member. Bulgaria's refusal to attribute the drone origin until debris recovery or a claim of responsibility highlights the ambiguity of hybrid operations and the difficulty of responding to attacks on civilian shipping. A confirmed state-actor attack would raise questions about maritime security and alliance consultations near NATO's southeastern flank.

Watch For

Monitor Bulgarian search and recovery efforts for drone debris, any claim of responsibility from Ukraine or Russia, the fate of the missing crew, and whether Zelenskyy's attribution prompts a Russian denial or comment. Watch for NATO or EU statements as evidence emerges, and for any further sea-drone attacks on merchant vessels in the western Black Sea.