Four decades ago, as millions around the world celebrated a royal wedding, Vishal Mehrotra vanished.
The eight-year-old boy – who lived in Putney, south-west London with his family – disappeared in the summer of 1981 after watching Charles and Diana's wedding procession.
Seven months later, his partial remains were found on an isolated farm in West Sussex, almost 50 miles away.
No-one has been ever been charged over Vishal's murder, despite calls from his family for police to reopen the case.
The latest episode of Channel 4's true-crime documentary series, In the Footsteps of Killers, investigates what could have happened to the young boy.
What happened to Vishal Mehrotra?
Little is known about Vishal's final moments. He disappeared on 29 July, 1981 while travelling home with his family from central London, where the royal wedding procession had taken place.
His skull and several rib bones were discovered months later – on 25 February, 1982 – by pigeon shooters in remote marshland at Durford Abbey Farm in Rogate, West Sussex.
At the inquest into Vishal's death, coroner Mark Calvert Lee recorded an open verdict but said "foul play" was likely.
Police said they interviewed 20,000 people over the case and checked 6,000 properties, but no-one has ever been brought to justice over the boy's murder.
In 2015, officers launched their first – and to date – only review into the case. The review, titled Operation Moor, was published in 2017.
Now, new evidence uncovered in the Channel 4 documentary potentially links Sidney Cooke, a notorious convicted paedophile, to Vishal's murder.
He is said to have been in Goodwood, West Sussex – around 13 miles away from Rogate – on the day the boy went missing.
The fairground worker was one of a 1980s gang known as a "Dirty Dozen" suspected of being responsible for abusing and killing young boys.
Now 95, he is serving two life sentences for a string of sex offences, and has been denied parole 10 times.
Criminologist David Wilson, who appears in the documentary, said: "I hope we've done enough to demonstrate to Sussex Police that they should regard Sidney Cooke as a prime suspect in the case."
Vishal's father, Vishambar Mehrotra, a retired magistrate, has previously blamed institutional racism for the police's failure to solve the crime.
In an interview with the BBC in 2021, he said: "I have no doubt that there is racism here, otherwise why would they try always to brush it under the carpet?
"When it comes to white children... they'll fly to Portugal, Germany, everywhere, and years have gone by, and they will still investigate and keep looking, and money doesn't seem to be a problem.
"But for my son, I can't see that they've done anything constructive by way of investigation at all."
A spokesman for the force said in response: "We firmly refute any suggestion that our enquiries over the past 40 years have been hampered or influenced in any way by 'institutional racism'.
"Reports of the 1982 investigation... make very clear the thorough and considered nature of detailed and painstaking work that officers and staff have carried out."