Rome, July 25 - The Vatican prelate arrested for alleged involvement in a bid to bring 20 million euros into Italy illegally has written to Pope Francis to say he is innocent. "I never laundered dirty money, I never stole, I tried to help someone who asked for help," Mons. Nunzio Scarano wrote in a letter from Rome's Regina Coeli prison dated July 20. Scarano, who until recently led a key Vatican accounting unit, was arrested in June in a probe over allegations he conspired with a former Italian spy and a financial broker to try to secretly repatriate the cash, allegedly the fruit of tax evasion by a family close to the prelate. The prelate, from the port city of Salerno near Naples, had been suspended a month before his arrest from his job as head of analytic accounts at the Holy See's asset-management agency APSA after being named in a separate probe into receiving money in Salerno. Police reportedly started sifting through his assets because of his suspiciously large financial holdings and artistic trove. He was arrested June 28 on suspicion of planning to elude customs controls along with Giovanni Maria Zito, a recently transferred agent in the AISI domestic intelligence agency, and financial broker Giovanni Carenzio. Police said Scarano and Zito set up a private jet to fly the cash for three Salerno-based shipowner brothers, the D'Amicos, whose family was friendly with Scarano. Zito is suspected of getting 400,000 euros for arranging cover for the flight, which never took place. The prelate has told prosecutors he "acted in good faith" and was only "trying to do a favour for the D'Amicos". The Vatican has said it would cooperate "fully" with the probe.