A series of politicians have been accused of abusing children, including late former Cabinet Minister Leon Brittan and Lib Dem Sir Cyril Smith.
The Mirror uncovered claims of a cover-up when one of Tony Blair’s ministers was suspected of being part of a child sex ring in Lambeth, South London, in the 1980s.
Scotland Yard is investigating.
Retired detective Clive Driscoll says he was stopped from investigating the Labour star in 1998 after he named the politician as a suspect.
In 2012 Operation Fairbank was launched to look into claims that there was a paedophile ring with links to government in response to information passed on by Labour MP Tom Watson.
Mr Watson used parliamentary privilege to allege that a file of evidence used to convict Peter Righton of importing child pornography in 1992 contained “clear intelligence” of a sex abuse gang linked to Number 10.
Last month documents emerged showing spy chiefs warned the Thatcher government in the 1980s that claims an MP had a “penchant for small boys” risked causing embarrassment.
Newly uncovered files show former MI5 director general Sir Antony Duff wrote to the then Cabinet Secretary Sir Robert Armstrong in 1986 over claims made by two sources about the MP.
Others named in secret files included Brittan, Thatcher aide Peter Morrison, former diplomat Peter Hayman and ex-minister William van Straubenzee.
In 2012, Operation Fairbank was set up in response to information passed on by Labour MP Tom Watson over an alleged child sex ring linked to government.
Fairbank spawned more inquiries.
Operation Midland is probing claims of a VIP paedophile ring in the 1970s and 80s.
Fernbridge is looking at allegations linked to the Elm Guest House in Barnes, South West London, during the 1980s.
Cayacos is probing cases linked to the Paedophile Information Exchange.
Lord Janner is to face a prosecution for child sex offences after Director of Public Prosecutions Alison Saunders was forced into a U-turn.
An independent review overturned Ms Saunders’ controversial decision that the former Labour peer should face no action over child abuse allegations because he is suffering from Alzheimer’s.