Bulgaria will join NATO's drone defense initiative by the end of October, following attacks on commercial vessels in the Black Sea

Bulgaria expects to join a NATO initiative to defend against drones by October 30, Defence Minister Dimitar Stoyanov said on Wednesday. The announcement comes after two commercial vessels were hit by drones off the Bulgarian coast on Tuesday, one of which sank.

The minister said during a parliamentary hearing that Sofia would participate in the Alliance’s project “as soon as possible.” Bulgaria is pushing to strengthen NATO’s defences in the Black Sea after a series of incidents highlighted the risks posed by the drone war between Russia and Ukraine to shipping near the Alliance’s southeastern flank.

The HS Dignity, flying the flag of Guinea-Bissau, sank after the attack, and 11 sailors are missing. Search-and-rescue operations resumed on Wednesday after being suspended because of bad weather and darkness.

On October 6, two other commercial vessels had been hit in the same waters. Bulgaria has not officially accused Russia, but Prime Minister Rumen Radev said Moscow was the main beneficiary of the attacks. Russia’s ambassador to Sofia did not rule out the possibility of a provocation organised by a third party. As pressure on maritime routes increases, the attacks are taking place amid Russia’s bombardment of Ukrainian Black Sea ports.