The pope's butler will stand trial for smuggling secret papers out of the Holy See in October.
But the Vatican's admission that there may be further arrests has sparked wild media speculation over who else may be involved.
While the Corriere della Sera newspaper believes there are three or four people who helped Paolo Gabriele get his hands on the documents, Il Messaggero daily says the real mole is a layman whose name begins with the letter “S”.
And Italy's news agency ANSA cites reliable Vatican sources to say there are around 20 people involved in the scandal Ä a charge the Holy See has rebuffed.
“There is absolutely no basis to the claim that there are 20 suspects,” Vatican press officer Ciro Benedettini said on Tuesday.
Earlier this month, a Vatican magistrate ruled that Gabriele must stand trial for stealing the documents from Pope Benedict XVI. Claudio Sciarpelletti, an analyst and computer programmer, was charged with complicity.
But while the butler insists he worked alone, many believe he is covering up for other whistleblowers still in action particularly considering several documents were leaked to newspapers even after Gabriele was arrested.
The reference to two other people suspected of aiding him, referred to only as “X” and “Y” in the prosecutor's statement to protect their identities as witnesses, has fuelled a race to dig up new suspects.
Among them are a certain “Y”, who knew Gabriele, an “E” whose office or home was searched by investigators, and “B”, the butler's spiritual adviser.
Italian journalist Gianfranco Nuzzi, who collected many of the leaked documents in a book entitiled “His Holiness” published in February, nicknamed his main source “Maria” but said around 20 whistleblowers were involved.