Explosive new revelations of the police and establishment cover-up over Cyril Smith’s paedophile past emerged last night. A retired police officer said the 29-stone Liberal MP was protected by a sex-offender sergeant after he was caught at a sex party with two boys. Smith walked free and the retired officer – then a probationary beat bobby – was threatened with the Official Secrets Act and told to stay silent by his colleague Don Mackintosh, who himself turned out to be a paedophile. Paedophile: A detective says he was ordered to cover up Cyril Smith's crimes by senior colleagues . Yesterday, after 27 years, the former Greater Manchester officer broke cover to reveal his anger amid growing fury over how Smith repeatedly escaped prosecution during four decades of appalling abuse. His revelations mean Smith escaped possible prosecution at least eight times after orders were made at the highest level to cover up his crimes. Last year the Daily Mail blew the lid off Smith’s perverted past when it serialised Simon Danczuk’s book, Smile For The Camera: The Double Life Of Cyril Smith. The Mail revealed how the Rochdale MP had repeatedly escaped police and court action for decades despite leaving a trail of young victims in his wake. Don Mackintosh, who turned out to be paedophile, threatened the officer with the Official Secrets Act and told him to stay silent . The strong suggestion has always been that the establishment conspired – via the police and security services – to protect the MP who was seen as a useful bulwark against the hard Left. Last night Greater Manchester Police announced a new inquiry into the claims. They were made just days after it was revealed that Smith had been arrested at a similarly sordid event in London but was let off. And yesterday another police force, Northamptonshire, disclosed that it, too, was probing suggestions that it let Smith off the hook in the 1980s when it discovered child pornography in his car. Labour MP Mr Danczuk said last night: ‘More police officers are now coming forward to share their anger and disgust at how there was simply no appetite to prosecute Cyril for child abuse. ‘Cyril Smith was a prolific abuser of children and I’ve no doubt that he was on the radar of a number of police forces.’ Earlier this week the independent police watchdog revealed it is overseeing 14 separate claims of cover-ups and corruption in historic sex abuse case by Scotland Yard. Prime Minister David Cameron has already guaranteed that police whistle-blowers will not be prosecuted under the Official Secrets Act if they come forward. The retired Greater Manchester officer was threatened with the Official Secrets Act after he discovered Smith at the party with a prolific sex offender and two drunk teenage boys in 1988. The officer said: ‘I had been in the force about six months. The occupier was about 70 and seemed an old granddad type. Earlier this week the independent police watchdog revealed it is overseeing 14 separate claims of cover-ups and corruption in historic sex abuse case by Scotland Yard . 'In the house was Cyril Smith and a police sergeant in civilian clothes. The officer identified himself and showed his warrant card, saying he was there “on other business”. ‘There seemed to be a party going on, with two young lads there. Smith and the officer left. The boys, aged about 14 to 15, were drunk. 'One was missing from a children’s home. I called for a van and took him back. The other lad walked off. ‘The old man was arrested and I took him to the main police station in Stockport.’ The following day, the officer says, he was called to a meeting by a senior officer and his mentoring officer, Sergeant Mackintosh, who was later exposed as a prolific child abuser and who was found hanged in his home last year. The officer said: ‘I was told I would break the Official Secrets Act if I told anyone. In no uncertain terms I was told to say nothing. They knew Smith was there and knew who he was.’ Greater Manchester Assistant Chief Constable Ian Wiggett said: ‘These fresh allegations will now be examined by Operation Clifton, a criminal investigation into how previous reports of child sexual abuse were handled or allegedly covered up. These allegations are concerning and will be treated seriously.’
Retired police officer said MP was protected by sex-offender sergeant . Was investigating MP but  probe was shut down by 'very senior officer'
Don Mackintosh, who turned out to be paedophile, told officer stay silent . Rochdale MP had repeatedly escaped police and court action for decades . Northamptonshire Police discovered child pornography in his car in 1980s .