More than 20 containers, some holding hazardous materials, fell into the Black Sea today from the container ship Contship Jet after sea drones hit it around noon off Cape Kaliakra. The ship has not sunk, but it is drifting south with a heavy list to starboard. The loose containers threaten shipping, the authorities said.

The Maritime Rescue Coordination Centre in Constanta reported the ship at 12:01 pm. Defence minister Dimitar Stoyanov announced the attack in Sofia, where defence ministers from Bulgaria, Romania and Turkey were meeting on maritime security. The crew had already left the ship on life rafts.

How it all started: All 18 crew rescued from container ship hit by drones off Kaliakra

Stoyanov said three sea drones attacked the ship. The Contship Jet sails under the Liberian flag and is run by a Greek company. It was travelling from Haifa in Israel to Constanta in Romania. It was about 16 nautical miles east of Kaliakra, outside Bulgaria's territorial waters, when it was hit. No one has publicly confirmed who is behind the attack.

The damage is serious, and all 18 crew members left the ship. Three navy vessels and a Border Police vessel were sent at once.

Eight of the sailors boarded a military boat. The other ten waited nearby in the ship's lifeboat. All 18 are now sailing to Varna, where border police officers and medical teams will meet them.

The transport, defence and interior ministries are running the operation jointly. Transport minister Georgi Peev thanked those who took part.

The cargo includes flammable liquids, flammable gases, non-flammable and non-toxic gases and other hazardous goods. The crew says there are 421 containers. A representative of the Greek company gave a capacity of about 700 TEU, which is a different unit for measuring capacity.

It is not known what each lost container held, whether hazardous materials have gone straight into the sea, or how much fuel is left in the tanks. By 3:20 pm the ship was still afloat and drifting south with the current. A decision on what to do with it is still to come.

It is the latest strike in the western Black Sea and off the Bulgarian coast. On 13 October, HS Dignity and Chelsea-3 were hit. The first sank. The second was towed to the port of Burgas, where inspections of its hull continued.