A Ukrainian drone strike on the Tuapse oil refinery on April 16 caused an oil spill, the Krasnodar Region operations center said.

A satellite image taken on April 19 showed an oil slick 1.5 miles from Tuapse, the operations center said.

Authorities estimated the contaminated area at 10,000 square meters (107,639 square feet). Containment booms have been deployed to limit the spread, and six vessels from the port of Tuapse are involved in the cleanup.

The drone strike on the port on April 16 also sent oil products into the Tuapse River, the operations center said. Some 750 meters (2,461 feet) of containment booms and specialized oil-collection equipment have been installed on the river.

A Ukrainian drone strike on the port of Tuapse set off a major fire, which the operations center reported extinguishing only in the afternoon of April 19. In the early hours of April 20, drones struck the port again, and Krasnodar Region authorities said another fire had broken out.

In early April, an oil slick was discovered off the coast of Anapa. The Krasnodar Region operations center said more than 200 birds were found dead or injured along the shore on April 11–12 as a result of the spill. The spill may have been caused by Ukrainian drone strikes on civilian vessels in the Black Sea and the Sea of Azov, the operations center said.

The environmental project Prozrachny Mir (Transparent World) established that the tanker Sofia was in the area where the spill occurred. The vessel is part of the shadow fleet carrying Russian oil in circumvention of sanctions, the independent Russian news outlet Verstka reported. Prozrachny Mir did not identify a possible cause of the spill. Ukraine has previously claimed strikes on shadow fleet tankers, including in the Black Sea.