VATICAN CITY A Vatican official already under investigation in a purported money-laundering plot involving the Vatican bank was arrested Friday in a separate operation: Prosecutors allege he tried to bring 20 million euros ($26 million) in cash into Italy from Switzerland aboard an Italian government plane, his lawyer said. Monsignor Nunzio Scarano, a recently suspended accountant in one of the Vatican's main financial departments, is accused of fraud, corruption and slander stemming from the plot, which never got off the ground, attorney Silverio Sica told The Associated Press. He said Scarano was a middleman in the operation: Friends had asked him to intervene with a broker, Giovanni Carenzio, to return 20 million euros they had given him to invest. Sica said Scarano persuaded Carenzio to return the money, and an Italian secret service agent, Giovanni Maria Zito, went to Switzerland to bring the cash back aboard an Italian government aircraft. Such a move would presumably prevent any reporting of the money coming into Italy. The operation failed because Carenzio reneged on the deal, Sica said. Zito, nevertheless, demanded his 400,000 euro commission. Scarano paid him an initial 200,000 euros by check, which Zito deposited, Sica said. But in a bid to not have the second check deposited at the bank, Scarano filed a report for a missing 200,000 check, even though he knew Zito had it, Sica said. Carenzio and Zito also were arrested Wednesday along with Scarano, Sica said. It's not the only troubles facing Scarano. Prosecutors in the southern city of Salerno have placed him under investigation for alleged money-laundering stemming from his account at the Vatican's bank, the Institute for Religious Works. Just this week, Pope Francis named a commission of inquiry into the bank to get to the bottom of the problems that have plagued it for decades and contributed to damaging the Vatican's reputation in global financial circles. That investigation concerns transactions Scarano made in 2009 in which he took 560,000 euros ($729,000) in cash out of his personal IOR bank account and carried it out of the Vatican and into Italy to help pay off a mortgage on his Salerno home. Vatican spokesman Father Federico Lombardi tells CBS News that Scarano was an accountant in the APSA, the Vatican department that manages the Holy See's real estate. To deposit the money into an Italian bank account -- and to prevent family members from finding out he had such a large chunk of cash -- he asked 56 close friends to accept 10,000 euros apiece in cash in exchange for a check or money transfer in the same amount, Sica said earlier this week. Scarano was then able to deposit the amounts in his Italian account. The original money came into Scarano's IOR account from donors who gave it to the prelate thinking they were funding a home for the terminally ill in Salerno, Sica said. He said the donors had "enormous" wealth and could offer such donations for his charitable efforts. He said Scarano had given the names of the donors to prosecutors and insisted the origin of the money was clean, that the transactions didn't constitute money-laundering, and that he only took the money "temporarily" for his personal use. The home for terminally ill hasn't been built, though the property has been identified, Sica said. "He declares himself absolutely innocent," Sica said of the Salerno investigation. The Vatican spokesman, the Rev. Federico Lombardi, told the AP earlier this week that the Vatican is taking the appropriate measures to deal with Scarano's case.