Dossier: Labour MP John Mann (pictured) has submitted an explosive dossier to police naming 22 politicians linked to historical child abuse

Police are investigating claims that at least five paedophile rings operating at the heart of Westminster were covered up.

Labour MP John Mann has submitted an explosive dossier to police naming 22 politicians – including three serving MPs and three serving members of the House of Lords – linked to historical child abuse.

Last night, he said the complexity of the criminality at the heart of the Establishment during the 1970s and 1980s had been underestimated.

The latest claims come after Mr Mann revealed in the Mail last week that he was aware of five investigations dropped by Scotland Yard into alleged VIP child abuse which took place over the last three decades.

Last night the Bassetlaw MP said: ‘There are at least five paedophile rings which involved MPs. Each of them involved at least one MP, some involved more, and these were groups of people who knew about the activities of one another.

‘In some cases I believe they committed abuse together.’ He told the Daily Telegraph: ‘Three of these figures were highly influential.’

The document submitted to police by Mr Mann also includes the names of 13 ex-ministers, including at least two who are claimed to have gone to ‘abuse parties’ held at Dolphin Square, the luxury riverside estate in Pimlico which has been home to dozens of MPs.

Mr Mann acted after receiving hundreds of reports from the public. Last month the Mail revealed how in 1989 as a young councillor in Lambeth, South London, Mr Mann uncovered evidence that a Tory Cabinet minister was allegedly involved.

He alerted police but was told three months later that the inquiry was being shelved on the orders of ‘those at the top’.

Now Mr Mann has compiled ‘credible’ information about 22 high-profile figures alleged to have committed offences between 1970 and the late-1990s.

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Estate: The document submitted to police by Mr Mann also includes the names of 13 ex-ministers, including at least two who are claimed to have gone to 'abuse parties' held at Dolphin Square, Pimlico

Probe: Met Police Deputy Assistant Commissioner Steve Rodhouse (pictured) has confirmed he is now assessing Mr Mann’s dossier as part of a raft of allegations that police acted inappropriately in relation to child abuse investigations covering a period from the mid-1970s up to 2005

The report names 14 Tory politicians, five Labour and three others. Mr Mann told the Daily Mail: ‘All of these allegations are historic but some of these people are still in positions of power, having been local councillors or MPs at the time. The offences span almost 30 years.

‘But I am still getting more information coming into me. There may be more.’ He added: ‘All those 22 names are worthy of investigation by the police. The evidence against half of them is very compelling.

Missing: Last month, it emerged another dossier, which named MP Cyril Smith (pictured) as being involved in abuse, had vanished

‘Some of them could definitely be prosecuted and I believe several of them were definitely child abusers.’

He told the Sunday Times: ‘Some of these victims have been ignored for years by the police and the Met really needs to step up to the mark now and do a proper job.’

Mr Mann also said he had received allegations that an organised crime gang and a celebrity were involved in the trafficking of young boys to abusers at Dolphin Square.

But many of the reports were never investigated at the time.

Met Police Deputy Assistant Commissioner Steve Rodhouse has confirmed he is now assessing Mr Mann’s dossier as part of a raft of allegations that police acted inappropriately in relation to child abuse investigations covering a period from the mid-1970s up to 2005.

Scotland Yard last week made a dramatic appeal for witnesses to three alleged child murders carried out by the Westminster paedophile ring, describing claims that a Conservative MP strangled a boy of 12 as ‘credible and true’.

An expert panel set up in July to look into historical child abuse is poised to be scrapped after being beset by problems, including the resignation of two chairmen.

Home Secretary Teresa May has told its eight members that a new body will be established with more powers.

Sharon Evans, who runs a children’s charity and is on the panel, said: ‘Halting the inquiry would send a very negative message to so many people who we have promised they can have confidence in us to do the right thing.’