Scotland Yard's failure to spot the lies of fantasist Carl Beech allowed him to continue committing paedophile offences while working as a school governor for three years, it has emerged.

In 2014 the Metropolitan Police launched Operation Midland when Beech, shielded under the name “Nick”, lied to detectives about being raped and tortured by a VIP paedophile gang in the late Seventies.

Police spent 18 months and £2.5 million investigating the claims of the former nurse and NHS manager, even raiding homes of some of those he had accused.

But while being supported by officers from the Met, Beech was downloading hundreds of appalling images of child abuse and taking surreptitious photographs and videos of youngsters in and near his home.

The offences for which he was convicted took place between November 2015 and November 2016 – the same period that Met officers were pursuing his false and malicious leads.