Vatican police have summonsed for questioning a senior priest and a former employee on suspicion of leaking confidential documents which are the basis of two new books on Vatican finances. The two, members of the commission set up by Pope Francis to reform church finances, are alleged to have passed sensitive details about their investigations to journalists.

Gianluigi Nuzzi, author of one of the books, Merchants in the Temple, was involved in the previous "Vatileaks" scandal the last Pope's butler Paolo Gabriele was found guilty of stealing and copying documents from the Pope's desk, sentenced to jail and then pardoned by Benedict XVI.

Mgr Lucio Angel Vallejo Balda, 54, of the Vatican's Prefecture for Economic Affairs and Francesca Chaouqui, 33, were arrested by Vatican police. Ms Chaouqui was released on Monday after she agreed to co-operate but Mgr Balda is still in custody. Bald was secretary and Chaouqui a member of the Commission for Reference on the Organisation of the Economic-Administrative Structure of the Holy See, set up by Pope Francis in 2013 and dissolved after it completed its investigation.

BBC Rome correspondent James Reynolds wrote: "The Vatican has a recurring problem with secrets and leaks."

He said Pope Francis promised a new kind of administration but by ordering a clean-up, inadvertently created material for a new round of leaks. "The Vatican now accuses two commission members of passing records of its discussions onto journalists."

The books are expected to reveal allegations of financial mismanagement as well as the extent of resistance to Pope Francis' attempts to reform the Vatican, Reynolds said.

The Vatican said the authorities detained and arrested two people over the weekend, in connection with the unauthorised sharing of confidential documents. "It must be remembered that divulging confidential documents is a crime under the criminal code of the Vatican City State," the Vatican said. "As for the books announced for the next few days it should be said clearly once again on this occasion as in the past, that they are the result of a serious betrayal of the trust placed in certain individuals by the Pope, and, as far as the authors are concerned, of an operation to draw advantage from a gravely unlawful act, ie, the delivery of confidential documents, an operation, the legal and possibly penal implications of which are currently the object of study in view of possible further measures by the Prosecutor's Office, which will resort, if necessary, to international cooperation."

The Vatican added: "Publications of this kind do not contribute in any way to the establishment of clarity and truth, but rather to the creation of confusion and partial and tendentious interpretations. We must absolutely avoid the mistake of thinking that this is a way to help the mission of the Pope."

In his weekly audience yesterday, Pope Francis continued to reflect on the importance of family for learning the values of forgiveness and reconciliation. "Each day, in the words of the Our Father, we ask God to forgive us and to grant us the grace to forgive others," he said.