Two commercial ships were struck by drones during the night of Monday to Tuesday in Bulgaria's exclusive economic zone in the Black Sea, one of which sank with its crew missing, announced Prime Minister Roumen Radev. According to his account, "around 3 a.m. this night, two commercial vessels were attacked by maritime and aerial drones" 70 nautical miles (130 kilometers) east of the city of Byala. The first ship, flying the Togo flag and heading north, sank. Its crew remains missing and its cargo is unknown. The second ship, which was carrying wheat and heading south, was also hit and a fire broke out on board. Its 18 crew members - eleven Turks and seven Indians - were able to be evacuated. Two were injured, one suffering from burns and the other from a head injury. According to the specialized website Maritime.bg, the ship that sank is the ALFA WATAN, and the second is the ABLE, flying the flag of the Palau. The Bulgarian freighter Dioskuria, which was in the area, saw the explosion on the first ship and went to the location, continued Roumen Radev. Its crew there found a boat and three overturned life rafts as well as life jackets but no member of the crew of the sunken ship has yet been found. "What is happening is significantly complicating navigation in the Black Sea, further increasing insurance premiums and making maritime traffic extremely difficult," emphasized Roumen Radev. The incident occurs the day after an attack on the Turkish cargo ship Royad Mammadov in the Romanian exclusive economic zone. Ukrainian President Volodymyr Zelensky accused Russia of striking the ship with two drones, which then sank. According to the press service of the Azerbaijani Ministry of Foreign Affairs, cited by Ria Novosti, the attack killed the Azerbaijani captain of the Royad Mammadov and caused one missing, also an Azerbaijani citizen. The incident on Tuesday is the first of this type in the Bulgarian exclusive economic zone in the Black Sea. In August, a drone had already exploded in the northeast of the country, near the Romanian border and a pipeline. Sofia had estimated that it was likely a model used by Ukrainian forces, Kiev asserting that no device had deliberately targeted Bulgaria. Discoveries of drones and other war-related devices have significantly increased in recent months in the Black Sea, particularly in Romanian, Bulgarian and Turkish waters. In Bulgaria, nearly 30 objects or fragments related to drones were found or destroyed between June and early September, according to reports from the Ministry of Defense. Throughout the Black Sea basin, the maritime risk assessment company Ambrey has recorded 56 discoveries of unexploded ordnance, drones and other unmanned devices between March and August, compared to 27 in the previous six months. At least a third of the devices carried a confirmed active payload. According to Ambrey, aerial and maritime drones now represent a floating danger greater than that of mines for navigation.