ROME — The Vatican on Monday announced interrogations and subsequent arrests of a cleric and of a laywoman, former insiders accused of passing confidential information on financial affairs to Italian journalists.

Spanish Monsignor Lucio Angel Vallejo Balda and Italian Francesca Chaouqui, who both served on a now-defunct financial reform commission, were identified by Vatican investigators as potential sources of leaked documents for two new books, set to hit the shelves in Italy this week, about Vatican finances.

Advance PR materials for both books have promised scores of previously secret Vatican documents, outlining various financial scandals.

According to a Vatican spokesman, both Vallejo and Chaouqui were called in on Saturday to the Vatican to testify, after “months of criminal investigation” about the “removal and dissemination of confidential documents.”

The priest is in a jail cell in the custody of Vatican police, known as “gendarmeria,” while Chaoqui was released on Sunday after assisting the authorities in their investigation.

The statement indicated that Chaoqui is cooperating in the probe.

Chaoqui is an independent PR consultant, while Vallejo is secretary of the Prefecture for the Economic Affairs of the Holy See, an office that formerly reviewed the work of all offices of the Vatican that manage finances.

He is also a member of a society of priests associated with the conservative Catholic group Opus Dei. As a diocesan priest, he doesn’t fall under the supervision of Opus Dei, nor does he work for it, but as a member of the society he receives spiritual guidance from the organization.

In a press statement released Monday in Spanish, Opus Dei expressed “surprise and pain” over the leak of confidential documents, adding that since they have no power over Vallejo, they know nothing beyond what was disclosed by the Vatican.

The prefecture’s former role now largely has been assumed by new financial overseers created as part of Francis’ reform efforts.

Both Vallejo and Chaoqui were members of the Pontifical Commission of Reference for the Organization of the Economic-Administrative Structures of the Holy See, known by its Italian acronym COSEA, set up by Pope Francis soon after his election in 2013 to study possible reforms of the Church’s financial structures.

The commission, on which Vallejo served as secretary and Chaoqui as a member, was dismantled after it delivered its final recommendations to the pontiff.

Two new offices were created as a result of COSEA’s recommendation: the Vatican’s Secretariat for the Economy, headed by Australian Cardinal George Pell, and the Council for the Economy, a supervisory board of cardinals and laypeople.

Neither Vallejo nor Chaoqui were named to any position in these new offices.

The Vatican statement said that the Office for the Promotion of Justice is currently studying the legal implications and the possible penalties, “resorting, if necessary, to international cooperation.”

That’s likely a reference to the fact that Vallejo is Spanish and Chaoqui Italian, so the Vatican might need help from authorities in those two countries if it decides to pursue criminal charges.

In effect, Vallejo and Chaoqui are accused of collaborating with Italian journalists Emiliano Fittipaldi and Gianluigi Nuzzi for their upcoming books, “Avarice: The Papers that Reveal Wealth, Scandals and Secrets in the Church of Francis” and “Via Crucis,” respectively.

Nuzzi is the journalist at the heart of the Vatileaks affair under Benedict XVI three years ago.

Regarding the two books, the Vatican statement said that “this time, as in the past, they’re the result of a serious betrayal of the pope’s trust,” and defined the books as “an operation to take advantage of a serious unlawful release of confidential documents.”

“Publications of this kind do not contribute in any way to establish clarity and truth, but rather to create confusion and partial and tendentious interpretations,” Vatican spokesman the Rev. Federico Lombardi said. “We must absolutely avoid the mistake of thinking that this is a way to help the mission of the Pope.”

When he released confidential documents in 2012, Nuzzi said he believed in Benedict’s desire to “purify” the Church, and wanted to help him by exposing betrayals by the people around him.

Those leaks led to the arrest and trial of a former papal butler and a Vatican computer technician. The butler, Paolo Gabriele, was later pardoned by Benedict XVI and released at the pontiff’s request.

After his election, Francis approved an amendment to the Vatican’s constitution, under the section “Crimes against the Security of the State.” According to those additions, the release of confidential information can be punishable by up to eight years in prison and a fine of 5,000 euro.

Fittipaldi’s book is scheduled for release Wednesday, and on the same day Nuzzi is to present his book at a Rome press conference.

Last week, Italian news reports said the Vatican’s gendarmeria, or police force, were investigating who had tampered with the computer of the Vatican’s auditor general, Libero Milone, a layman.

The Vatican on Monday confirmed that there was an investigation into the tampering, but declined to say if that incident was related to the two arrests.

Material from the Associated Press was used in this report.