He later passed some to journalist Gianluigi Nuzzi, who this year released a best-selling book detailing scandals and infighting within the Vatican.

BBC: Pope Benedict pardons former butler Paolo Gabriele

Gabriele was arrested in May, following a Vatican investigation into how the pope's private documents appeared in the book "Sua Santita" ("His Holiness"), by Italian journalist Gianluigi Nuzzi.

CNN: Pope pardons ex-butler jailed over Vatican leaks

The Vatican butler was arrested in May, accused of passing papal correspondence to journalist Gianluigi Nuzzi, whose book His Holiness: The Secret Papers Of Pope Benedict XVI was published that month.

BBC: Pope's ex-butler Gabriele 'kept top secret papers'

Last month, the Vatican gave Cardinal Julian Herranz a "pontifical mandate" to uncover the source of hundreds of personal letters and confidential documents given to Gianluigi Nuzzi, an Italian journalist and author of "Sua Santita, " a book that translates to "His Holiness" and includes the documents.

CNN: Vatican: Pope not resigning over alleged papers leak

Last month, the Vatican gave Cardinal Julian Herranz a "pontifical mandate" to uncover the source of hundreds of personal letters and confidential documents that have been released to Gianluigi Nuzzi, an Italian journalist and author of "Sua Santita, " a book that translates to "His Holiness" and includes the documents.

CNN: No cardinal suspected of pope papers leak, Vatican insists