An illegal dumping of cargo oil at sea could have caused the deaths of hundreds of sea birds along England's south coast, an expert said.
Thousands of birds have been washed to shore along coastline that stretches from West Sussex to Cornwall after being covered in a sticky, oily substance.
Wildlife experts and volunteers raced to the shoreline to save as many birds as possible, and hundreds - mostly guillemots - are now being treated at RSPCA centres.
Scientists from the Environment Agency identified the mystery substance as a refined mineral oil, but not from an animal or vegetable-based oil.
Some kind of accident such as a leaky gearbox or a broken pipe is the most likely cause of a mineral oil spill, but it is unusual that it would cause this much havoc.
So that makes one think it could be an illegal dump of cargo oil - oil that is being transported rather than used in the working of the ship.
This could happen if there was illegal washing out of tanks at sea. Some unscrupulous operators, and they are rare, flush the tanks out there because it is cheaper and easier than doing it in dock. It is illegal and quite harmful.
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