Officials took new seawater samples today at three places on the Black Sea coast, the Ministry of Environment and Water said. One is the Budzhaka area near Sozopol. Teams are looking for oil pollution after drone attacks on ships.

This is the third round of sampling in a row. The Black Sea Basin Directorate will announce the results once laboratory tests are done. The ministry promised to inform the public promptly.

The Black Sea Basin Directorate and the regional laboratories of the Executive Environment Agency in Varna and Burgas are taking the samples. The other two sites are Bolata bay in Kavarna municipality and Cape St Athanasius near Byala.

Environment and water minister Rositsa Karamfilova has ordered regular checks on the sea water after the incidents with ships in the Black Sea.

In early October, sea and air drones attacked two merchant ships in Bulgaria's exclusive economic zone in the Black Sea. The ministry then began checking the water in the area.

On Tuesday, prime minister Rumen Radev said drones had attacked two more ships.