LONDON — An alleged pedophile ring at the heart of British politics is to be investigated after claims of a decades-long cover-up that continued until this week.

The government finally succumbed to pressure Monday and announced that a public inquiry would examine allegations that at least 10 current and former MPs were accused of abusing children but escaped with little or no investigation into their alleged crimes. A second, even broader inquiry will look into the suppression of child-abuse allegations against public officials spanning a generation. The unprecedented scrutiny of British public life will include an examination of practices at churches, schools, the NHS, the BBC, and inside the police and security services.

At the center of allegations about a political cover-up is a nondescript Edwardian terraced house in West London. What looked like a small suburban hotel, called the Elm Guest House, was closed down after a police raid in the 1980s amid allegations that it operated as a brothel specializing in underage boys. Scotland Yard officers are now in possession of a list of alleged visitors that includes MPs, a senior police officer, a Buckingham House attendant, two musicians, and an MI5 officer.

Sir Anthony Blunt, the infamous Cold War double agent, and Cyril Smith, a 400-pound Liberal MP, were among those alleged to have frequented the establishment before its closure. Smith, who died in 2010, has been the subject of numerous posthumous sex-abuse allegations.

Norman Tebbit, a Cabinet minister under Margaret Thatcher, told the BBC on Sunday that there “may well have been” a cover-up. “It was almost unconscious. It was the thing that people did,” he said. “At that time I think most people would have thought that the establishment, the system, was to be protected, and if a few things had gone wrong here and there that it was more important to protect the system.”

Simon Danczuk, a Labour MP whose investigations into child abuse have included writing a book on Smith’s alleged crimes, said the cover-up was not limited to the 1980s. He claimed to have been placed under intense pressure not to name names when he gave evidence to a parliamentary committee last week. He said party whips, lords, and MPs had been among those “cajoling, arm-twisting and bullying” participants not to identify any living politicians.

“A Tory minister stepped out of the shadows to confront me,” Danczuk wrote in The Guardian. “He blocked my way and ushered me to one side. He warned me to think very carefully about what I was going to say.”

Ignoring the warnings, Danczuk went on record to claim that Leon Brittan, then home secretary—the minister overseeing law and order—had been passed a dossier of sex allegations against politicians in 1983 but failed to follow up on the claims. The Home Office, which was asked to look into the fate of the dossier last year, has conceded that 114 “potentially relevant files” have been lost or destroyed.

It has subsequently emerged that Brittan was himself the subject of a rape allegation, which police initially dismissed before the director of public prosecutions urged them to reconsider this month. Brittan described the allegations as “wholly without foundation” on Monday.

Danczuk and fellow Labour MP Tom Watson have been demanding action to shine a light on allegations of the misuse of power. For years, calls for further investigations into the Elm Guest House were relegated to the websites of citizen journalists found well outside the mainstream media.

Watson’s determination to expose the truth about pedophiles in Westminster was praised in the Commons on Monday. He told The Daily Beast last week that his campaign would have benefited from the support of senior media executives. Once Rebekah Brooks had been cleared of phone hacking charges, Watson suggested that she could help lead the charge. “There is a major citizen-led inquiry into historical cases of organized sexual abuse,” he said. “I'm sure they would welcome her support for the campaign.”

His work finally bore fruit when Theresa May, the current home secretary, announced the formation of the inquiries Monday. “I want to be clear that the inquiry panel will have access to all the government papers, reviews, and reports it needs,” she said.

May also attempted to address the concerns of Danczuk and Watson, who said they were worried that law enforcement officials might be bound by gagging clauses in severance packages or the Official Secrets Act. “It is only if people can speak openly that we are going to get to the bottom of these matters,” she said.