The hiring of Giuseppe Pignatone, who this year retired as chief prosecutor of Rome, came after the Vatican announced this week that a raid was carried out “to acquire documents and electronic devices” from the offices of its Secretariat of State, its most senior administrative body, as well as the offices of its financial watchdog.

The Vatican said that the raids had been carried out after a complaint was made by the Institute for the Works of Religion, the Vatican’s bank, over the summer “regarding financial transactions carried out over time”.

When contacted the Vatican declined to confirm the identities of the five Vatican employees who have been suspended pending an investigation, or what transactions the raids were linked to.

Italy’s L’Espresso magazine published a copy of a Vatican police directive distributed to staff that identified five people it claimed were the individuals involved, including their photographs. The directive said that the suspicious transactions were linked to real estate investments made by the Vatican’s Secretariat of State in London.

Yet the public nature of the announcement shocked many within the Vatican.

The official Vatican news website published an editorial denouncing the Vatican press office’s decision to publish news of the raids. It said the publicity subjected the accused to “media pillory” and called for an official investigation into how the news was released.

However it also said that the raids “prove concretely that the processes begun by Pope Benedict XVI, and carried out by Pope Francis, really work. It proves that the new laws of Vatican City State are being applied”.

Mr Pignatone previously served as a prosecutor in Sicily and Calabria where he conducted investigations into the Cosa Nostra and ‘Ndrangheta crime organisations. As head of the Vatican’s criminal tribunal he will have responsibility for crimes that occur within the Vatican or by its diplomats.

The latest scandal to hit the Vatican comes as Pope Francis struggles to cast off the legacy of financial impropriety which has dogged the reputation of the Holy See for decades.

In 2017 the Vatican’s first auditor general Libero Milone stepped down in mysterious circumstances, accusing powerful figures within the Holy See of blocking his investigations into financial crimes.

At the time the Vatican said it strongly denied the claims of the former Deloitte partner, who had been hired by Pope Francis in 2015 as part of his financial reforms.