A trial of two Italian journalists and three other people accused of leaking and publishing confidential Vatican documents has got under way at the Holy See, drawing condemnation from media watchdogs. Reporters Gianluigi Nuzzi and Emiliano Fittipaldi said the case against them was one against press freedom, as they appeared before a Vatican court.

Prosecutors allege the two violated Vatican laws by writing books based on confidential Holy See documents that detailed mismanagement in the tiny state. If convicted, they face up to eight years in prison. "I am not afraid, I am calm," Nuzzi wrote on Facebook, minutes before the first hearing.

"I have no intention to repent. It's those who squandered money of the poor and weak, those who enjoy themselves in super attics at worshippers' expenses that will have to repent," he added in reference to revelations contained in the two tomes, Fittipaldi's Avarice and his own Merchants in the Temple (Via Crucis in Italian). "I will be in court at the Vatican to denounce a system of censorship that bans freedom of thought and information."

He was echoed by Fittipaldi who described the trial as an attack on press freedom. "In no other part of the world, at least in the part of the world that considers itself democratic, is there a crime of a scoop, a crime of publishing news," he told AP.

Three other people, a monsignor, his assistant and a PR, are also facing charges in connection with the case. Father Lucio Angel Vallejo Balda, Nicola Maio and Francesca Chaouqui are accused of being the whistle-blowers that provided Nuzzi and Fittipaldi with material for their books.

All three worked on a papal committee set up by Pope Francis to overhaul the Vatican's financial administration in 2013. Avarice and Merchants in the Temple are heavily based on documents from that committee.

Chaouqui and Vallejo were arrested earlier in November. The PR has denied any wrongdoing and was released after she agreed to cooperate with authorities. "I challenged the dirt as Francis asked me within those walls and I should fear lies now?" she defiantly wrote on Facebook ahead of the trial. Vallejo is still to comment on the case.

Among revelations contained in the volumes are allegations that €200,000 (£140,000, $212,000)in donations to a child hospital were used to refurbish the Rome attic of controversial cardinal Tarcisio Bertone and that religious groups paid up to €750,000 to secure sainthood for their favourite candidates.

Watchdogs including the Committee to Protect Journalists (CPJ) and the Organization for Security and Cooperation in Europe (OSCE) urged the Holy See to drop the case against Nuzzi and Fittipaldi.

"Journalists should be allowed to carry out their role as watchdog and investigate alleged wrongdoing without fear of repercussions," CPJ Europe and Central Asia Program Coordinator Nina Ognianova said.

OSCE media freedom representative Dunja Mijatovic said: "Journalists must be allowed to report on issues of public interest and to protect their confidential sources."

The case comes three years after Benedict XVI's butler was found guilty of another famous leak of confidential documents revealing mismanagement, corruption and bitter power struggles inside the Holy See. Also in that case the recipient of the stash of confidential material was Nuzzi.