The daughter of a man allegedly murdered to prevent him exposing a council paedophile ring has told of her anger that a report on the abuse was ‘covered up’.

Kiddist Forsythe was born three months after her father Bulic was beaten to death in his flat, which was then torched.

Mr Forsythe, 42, was a manager at the housing department of Lambeth Council in south London, which is now the focus of an investigation into historic sex abuse claims.

Bulic Forsythe (left), a manager at Lambeth council, was killed shortly after he told colleagues he wanted to expose an alleged paedophile ring. His daughter Kiddist (right) says her family are determined to get justice

Trainee lawyer Miss Forsythe, 21, believes he was killed because he found out about the abuse and planned to blow the whistle.

She has now been shown a report from an internal 1993 council probe proving other colleagues knew about the paedophile activities.

It describes claims of rape, sex assaults and the swapping of child abuse videos. Lambeth staff, police and politicians are implicated. But the report was never published and was not handed to police at the time. Miss Forsythe said she was ‘shocked’ at its contents.

‘Some of the stuff in there is quite harrowing,’ she said. ‘I am angry – I think everyone should be angry, not just me because I’ve a personal interest.

‘For this to go under the radar for 20 years is terrible.’

Speaking of her father, she said: ‘From all accounts, he was a lovely, kind, patient man. It did seem he was proud of his work and wanted to do the right thing. So it seems he did know something, and he was getting ready to blow the whistle.’

Victims were taken to this Lambeth council housing department building in the 1980s and 1990s and abused in the basement, according to claims made in a report kept secret at the time

Mr Forsythe’s death in 1993 was the subject of a BBC Crimewatch appeal, which revealed three men were seen carrying files from his flat in Clapham the following day. His bedroom was later torched and the oven turned on.

His widow, Dawn, has said she believed someone ‘wanted to shut him up’.

John Mann MP, who investigated the claims in the 1980s, said he's certain there was a cover-up and has urged any with information to come forward

The Lambeth report documents claim senior figures in the council were using its premises for the rape of women and children.

They allegedly used the basement of Lambeth’s housing headquarters because ‘sexual assault could be performed without fear of interruption’.

A senior staff member is accused in the report of watching material with ‘sadistic, bestial and paedophile themes’ which ‘may have been home-produced by staff or people with whom they associated’. A female employee reportedly claimed she was raped on council property alongside children and animals by senior figures in the council.

The report states: ‘The murder of Bulic Forsythe was seen by some witnesses as a possible outcome for anyone who strayed too far in their investigation or for those who asked too many questions.’ Three senior members of staff were sacked but no police investigation took place, despite the report recommending a criminal inquiry.

Dr Nigel Goldie, former Lambeth assistant director of social services, said yesterday he believed this was because of a culture of wanting to keep things ‘behind closed doors’.

‘People will be incredulous,’ he said. ‘How can it be that a report raising all sorts of issues of sexual abuse and a range of different kinds of rather weird practices could not have led to a more thorough investigation.’

The Metropolitan Police said it was considering the report as part of Operation Trinity, its investigation into alleged abuse at children’s homes in the borough.