The dad of an eight-year-old boy murdered almost 39 years ago is pleading with police to re-open the case.
Vishal Mehrotra disappeared from west London in 1981 and his remains were found seven months later.
His father Vishambar said information obtained by the BBC, including interviews with convicted paedophiles, was a "major revelation".
Sussex Police said they currently had no plans to re-investigate.
Vishal went missing on the day of the Royal Wedding of Prince Charles and Lady Diana Spencer - 29 July 1981.
He and his family had been in central London watching the parade and were on their way home to Putney when he disappeared.
His remains were found by pigeon shooters the following year in remote marshland at a farm in Rogate, near the Hampshire-West Sussex border.
At an inquest into his death in 1983 an open verdict was recorded but West Sussex Coroner Mark Calvert Lee said foul play was likely.
Sussex Police confirmed three men who were jailed for sexual abuse of children at a school in the south east of England were questioned in 2019 about Vishal's murder.
One of those men revealed he wrote a confidential report in 1983 about caring for Asian children in the UK which he titled "Vishal".
Despite this, Sussex Police said they had no plans on making any more inquiries.
Vishambar Mehrotra told the BBC: "Why would my son's name appear on a document more or less contemporaneously written by a paedophile which is in the possession of the police and the police came to the conclusion that there is nothing more to investigate?"
Sussex Police visited Mr Mehrotra two weeks ago to tell him they interviewed the men last year in connection with his son's murder.
They told him there were no significant developments and did not disclose details about the document titled "Vishal".
The force said it would not disclose or confirm the content of the information considered last year but said the inquiries officers carried out in relation to it were thorough.
A spokesman said: "The case remains unresolved and like all such cases is subject of regular assessment every two years to establish if there are any potential new lines of inquiry.
"Even after nearly 40 years, we will continue to take any opportunity to pursue any new lines of inquiry that might lead to justice being obtained for Vishal and his family."
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