A swan owned by the Queen has been found barbecued on the banks of the Thames in the shadow of Windsor Castle.
The Royal bird was found on Baths Island, in the middle of a picnic area popular with children and tourists.
It had been cooked with its feathers still attached, and meat had been stripped from its carcass.
Park wardens made the gruesome discovery in Windsor, Berkshire, at 3pm on Sunday, and called Swan Lifeline, which cares for sick or injured birds along the Thames.
Wendy Hermon, treatment centre co-ordinator for Swan Lifeline, told Sky News Online: "They were in the middle of their walkabout when they phoned us to say we've found what looks like the remains of a cooked swan.
"It's absolutely disgusting doing something like that. We've heard for years that sort of thing goes on; we've never actually seen it.
"But to barbecue a swan and leave its body in the centre of Windsor with all the tourists and children about is absolutely disgraceful."
She added: "We have shot swans from time to time, and swans attacked by dogs and foxes, but that's nature and we accept it.
"But when it's something like this it's disgusting. It was so so selfish and wrong just to leave it there in the middle of the grass.
"They'd stripped the meat off it, they'd carved the breasts off the bones. There were no remains of a fire, but they're always having barbecues up there even though they're not allowed.
"And I think that's why the park wardens had gone up there, to tell people not to barbecue."
She said the carcass was taken back to the Swan Lifeline centre to be cremated.
David Barber, The Queen’s Swan Marker, said he was appalled by the incident.
"It's an absolutely shocking situation and as far as I'm concerned the police are investigating this," he told Sky News.
"All swans are considered by people to be Royal birds and it's quite a shock to people to see this in a middle of a picnic lawn in a public area."
He said all swans on the Thames belong to the Queen, apart from those owned by the Vintners and Dyers livery companies.
The suspects face a maximum six months jail sentence and £5,000 fine because wild swans are protected under the Wildlife and Countryside Act 1981.
But Mr Barber said if the dead swan is claimed by the Crown, the suspects could also be prosecuted for damaging Crown property.
The first written record of the swan as a Royal bird dates back to the 12th century.
Cygnets were highly prized for their gourmet qualities and were often served at banquets. Anyone caught stealing the birds was severely punished.