The chief civil servant at Britain's Home Office has pledged to engage a senior lawyer to review the handling of allegations of child sex abuse against senior public figures three decades ago.
Mark Sedwill, permanent secretary at the Home Office, said in a letter to Keith Vaz, chairman of Parliament's Home Affairs Committee, that an independent investigator had determined that 114 potentially relevant files on the matter were "presumed destroyed, missing or not found".
Sedwill also wrote to Prime Minister David Cameron saying that he would appoint a lawyer to probe the issue further this week.
Sedwill commissioned an investigation in February last year after a query from Labour lawmaker Tom Watson, appointing an "experienced investigator".
"I asked the investigator to review all relevant papers received by the department concerning organised child sex abuse and whether the appropriate action was taken throughout the period 1979-99," he wrote in his letter to Vaz. Sedwill commissioned the new review "to be reassured that the conclusions of the investigation remain valid".
Part of the investigation last year centred on a dossier presented in 1983 by now-deceased Conservative lawmaker Geoffrey Dickens to Leon Brittan, who was the home secretary at the time.
While the probe could not locate that file, it did find correspondence from Brittan to Dickens saying his allegations had been considered and some had been referred to "the proper authorities", Sedwill said.
Separately, it was claimed that Brittan was questioned by police last month over a historical allegation of rape.
Detectives were said to be investigating an allegation that Brittan assaulted a woman at an address in London in 1967.
Additional reporting by The Guardian