A sunken boat in Kingston that was destroyed by a fire is believed to be leaking oil into the Thames.
Swans have also been spotted with their underside covered in the thick liquid.
Toby MacGregor, who photographed the situation near the Ram pub, said: “I reported this to the Environmental Agency on Saturday and they still haven’t put an oil absorbent boom to reduce the environmental impact.
“It’s really sad to see the swans covered in oil with their feathers matted and waterlogged.
“Not sure what actions we can take to help these poor birds?”
A spokesman for the EA said: “We are working with the owner of the boat for him to remove the boat from the site.”
The Swan Sanctuary said the swans are not in any immediate danger.
The boat, a Caribbean cruiser, was engulfed by flames just before midnight on December 6.
Eight people were evacuated from nearby flats as a precaution.
The fire, which did not result in any injuries, involved gas cylinders according to London Fire Brigade.
The cause of the fire is believed to be accidental.
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