An initial check after the strike on the container ship found no signs of pollution in the sea, Bulgaria's environment ministry (MOEW) says. Tomorrow teams will take water samples at five points along the coast for laboratory tests.

Sea drones hit the container ship CONTSHIP JET around noon today. The transport and communications ministry (MTC) reported the rescue of the crew.

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

Defence minister Dimitar Stoyanov said three sea drones struck the ship in the contiguous zone, about 21 nautical miles south-east of Shabla. The MTC press office said the ship was hit about 17 nautical miles east of Cape Kaliakra.

Officials checked the Shabla area and Bolata bay near Cape Kaliakra. They found no oil slicks and no visible change on the water surface. The environment ministry said these findings are only initial and lab tests will add to them. The tests aim to show whether there is pollution, and whether the water quality has changed in a way the eye cannot see.

The environment, defence and transport ministries are coordinating their work. Defence ministry teams took samples today at two points in Bulgarian territorial waters.

Tomorrow teams from the Black Sea Basin Directorate and the Executive Environment Agency (EEA) will take water samples at Durankulak, Shabla, Cape Kaliakra, Byala and Sozopol. Defence ministry teams will also take samples near the container ship.

The EEA's regional laboratories in Varna and Burgas will test the samples taken by the military and near the ship. They will look for oil products, polychlorinated biphenyls (PCBs) and metals, as well as other physical and chemical markers of water quality.

The Maritime Rescue Coordination Centre in Constanta raised the alarm at 12:01. At 12:13 the sailors left the ship and a search and rescue operation was declared. Three Navy vessels and one Border Police General Directorate ship headed to the area.

At 12:53 eight sailors were taken aboard a Navy boat, while the other ten were in the ship's lifeboat. All 18 crew members have been rescued. A Navy ship is taking them to Varna, where Border Police and medical teams are preparing to receive them.

The ship sails under the Liberian flag and was travelling from the Israeli port of Haifa to Constanta in Romania. The crew say there were 421 containers on board. The ship's manifest lists lithium-ion batteries, corrosive liquids and acids, flammable liquids including ethanol solutions, household chemicals, plastics, food, building materials, timber, machinery and industrial parts.