An Italian journalist who is under criminal investigation by the Vatican for publishing a book said he refused to answer the Vatican prosecutors' questions during an interrogation this week.

Emiliano Fittipaldi, author of "Avarice," which is based on leaked Vatican documents, said he agreed to go to the Vatican on Monday after being formally summoned for an interrogation because he wanted to understand exactly what he was accused of.

But he told reporters Tuesday he refused to answer the prosecutors' questions about the case, citing the protections journalists enjoy in Italy to protect their sources — protections that don't exist in the Vatican legal code.

Another Italian journalist who wrote a second book and is also under investigation by the Vatican, Gianluigi Nuzzi, refused to appear for questioning.