"There are leakers among the cardinals but the Secretariat of State could not say that, so they arrested the servant, Paolo, who was only delivering letters on behalf of others," La Repubblica quoted one alleged whistleblower as saying.
The Secretariat of State is run by Cardinal Tarcisio Bertone, the pope's powerful right-hand man, and the scandal appears to involve a power struggle between his allies and enemies, reminiscent of Renaissance conspiracies in the Vatican.
Documents leaked over the last few months included letters by an archbishop who was transferred to Washington by Bertone after blowing the whistle on what he saw as a web of corruption in a memo that put a number of cardinals in a bad light. Other documents alleged internal conflicts over the Vatican bank.