A Vatican spokesman said a suspect in the leaks was being questioned by Vatican magistrates.
Earlier this year, sensitive Church documents were leaked to the Italian media, who dubbed the scandal "Vatileaks," ANSA reported.
The news service said the documents included letters to the pope and Vatican Secretary of State Cardinal Tarcisio Bertone from Maria Vigano, the Vatican's ambassador in Washington.
Vigano was deputy governor of Vatican City when the documents, which contained allegations of corruption in Vatican management, were written.
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