A barrister will not face criminal charges after her dog attacked a seal nicknamed Freddie Mercury, leading to the animal being euthanised.

The young common seal, which had been given the name in honour of the late Queen singer by walkers in Barnes, west London, was bitten by the dog on Sunday.

Freddie was found to have a fractured flipper and a dislocated joint, with veterinarians at South Essex Wildlife Hospital concluding the “only ethical and fair option” was to put him to sleep.

The dog’s owner, Rebecca Sabben-Clare QC, has since said she was “heartbroken by this terrible accident” and apologised.

On Wednesday, Miss Sabben-Clare said: “As an animal lover, I fully understand the dismay that has been expressed. I apologise unreservedly for what happened.

“In hindsight, I wish, of course, that the dog had been on a lead but at the time it did not seem necessary.

“I am hugely grateful to all those who helped at the scene. They were heroic.”

Miss Sabben-Clare said she had made a donation to the wildlife hospital which treated Freddie, praising the “wonderful work” it does.

On Wednesday, the Metropolitan Police said there would be no criminal action or further investigation taken by police.

A force spokesperson said: “Police have investigated the death of a seal after it was injured by a dog on the River Thames near Hammersmith Bridge.

“Officers attended the location at approximately 12.39hrs on Sunday March 21 along with colleagues from the London Fire Brigade.

“Following the investigation, there will be no further criminal investigation or criminal action taken by police in regards to this matter.”

Miss Sabben-Clare was interviewed by the RSPCA, who said as it was not a case of deliberate cruelty it was not an incident they would investigate.

The charity said it was “deeply saddened” by the incident and that it highlighted the need to keep dogs on leads near wild animals.

An RSPCA spokesperson said: “We investigate animal welfare offences. Dog attacks on animals would become an animal welfare offence if it was done deliberately.

“If no offences have been committed under relevant animal welfare acts we are unable to take incidents further. Offences involving dogs out of control are investigated by the police.

“In this instance, we spoke to the owner and as this was not a case of deliberate cruelty, it is not an offence we would investigate.”