A health professional who reported widespread child abuse at a school for vulnerable boys has told the BBC he believes his report was "suppressed".
Phil Shepherd visited the Knowl View School in Rochdale in 1991 and is to give evidence to an independent inquiry set up by the council.
He says he was told boys as young as eight were working as prostitutes while others had been "forced" to have sex.
Rochdale Council says it cannot comment ahead of the inquiry.
In April, police began a fresh investigation into allegations of abuse and a possible cover-up at Knowl View. The separate independent inquiry is investigating whether Rochdale Council could have done more.
Mr Shepherd, who attended Knowl View to offer sex education training for staff, told the BBC what he was told by them was a "bombshell".
"I wrote a report. I imagined it blowing up anytime soon. The fact that it didn't has always amazed me," he said.
The BBC has obtained a copy of Mr Shepherd's original report from 1991.
In it, he wrote: "…parents of children at the school would be horrified were the facts to be known.
"Unless some incisive action is taken soon it is more than likely that this activity will become a public scandal".
He writes in the introduction that "most of the day was spent with the staff voicing very strong feelings about problems at the school, in particular concerns about the safety and behaviour of some of the 36 boys".
He goes on to detail claims that men from as far away as Sheffield were travelling to Rochdale to abuse five boys aged between eight and 13 who were working as prostitutes at public toilets. He wrote at the time that police were "aware of the problem" but "what action has been taken is not known".
Mr Shepherd adds that there had apparently been efforts made to reform the "disorganised" school but his own attempts to "clarify what action" had been taken by agencies involved with the pupils had "so far been fruitless".
Knowl View School opened in 1969 and closed in the mid-1990s.
It was a residential school for vulnerable boys. At various points Cyril Smith, the late MP for Rochdale who has been accused of abusing boys, was a governor.
Mr Shepherd says he will use the opportunity of giving evidence to the council inquiry to say his report was ignored, and believes a cover-up is the only explanation.
"To be honest with you, I can't see any other reason that it hasn't come out and it wasn't dealt with effectively at the time," he said.
The BBC has seen documents that seem to show his report was passed onto other departments within the council, and to the police.
A council investigation was requested a month after Mr Shepherd's report. Despite it detailing abuse and prostitution, an investigation was ruled out six weeks later.
Mr Shepherd believes not enough was done to help the children.
"I still find it hard to believe. I'm looking for an alternative to cover-up. It could've been repressed, it could've been hidden, it could have been locked away. I just don't understand."
It is 23 years since Mr Shepherd visited the school.
Asked whether he thought he should have done more at the time, he said: "I've looked back and thought about it often - certainly more recently - and thought I possibly should've done more. I'm not sure what it would've been."
Two other reports were written about Knowl View in the early 1990s. They were commissioned by Rochdale Council and, like Mr Shepherd's report, detailed the abuse of boys.
Other documents suggest changes were being planned but some at the school say not enough was done.
Martin Digan was a social worker at Knowl View and believes all three reports were ignored; that parents were never told what had happened to their boys.
"It's a complete cover-up by Rochdale Council. Not one parent has seen a report; not one of the children has seen a report."
He too will give evidence to the independent council inquiry. He says he hopes the children will get the justice they have been denied.
'I feel very strongly. By no means have they had any justice yet.'
A number of boys who were at Knowl View are taking legal action.
Solicitor Alan Collins, from Slater & Gordon, is representing two of them. He says Mr Shepherd's belief his report was covered up is important.
"It is very significant if Mr Shepherd is of the opinion that his report was covered up. There he was, at the heart of an investigation and here we are in 2014 with him saying he believes that there was a cover-up."
Mr Collins added: "All the evidence so far points to that report remaining under the radar, and with it, the legitimate question can be asked: Was there a cover-up?"
Detectives investigating the allegations of abuse at Knowl View say they have identified more than 21 suspects, including Smith. Ten people have said they were abused.
Asked about documents seen by the BBC detailing abuse allegations at the school, Chief Superintendent Russ Jackson of Greater Manchester Police said they would now "be treated very differently and prompt a very different response".
One former pupil called Peter says he was abused by a staff member on the first day he arrived at the school at the age of 11.
He said the "worst nights" were when people were brought from outside the school.
"We were raped. There was a flat. We were taken there and plied with drink and raped."
The independent inquiry into the role of Rochdale Council is due to report at the end of July.