A Russian tanker has been smashed in half by five-metre high waves near the Black Sea, spilling 1,300 tonnes of fuel oil.
Russia’s environmental protection agency called it a “disaster” and green campaigners described it as an “ecological catastrophe”.
Two other cargo ships, each carrying 2,000 tonnes of sulphur, sank in the area and eight crew members from one of the vessels are missing.
The oil spill happened in the Kerch Strait, between the Azov and Black Seas.
Some 300 kilometres west, high winds sank a cargo boat with 17 sailors on board off Ukraine’s Black Sea coast. Two have been rescued but 15 are still missing.
As wind speeds topped 108 kilometres an hour, several vessels were reported stranded in and around the Russian port of Kavkaz.
More than 40 ships have been evacuated from the port and 17 have been forced to stay because of the dangerous weather.
Forecasters say conditions are due to worsen overnight.
Russia and Ukraine have set up a joint crisis centre to deal with Sunday’s disaster and aircraft will fly to the area as soon as the weather allows.