(CNN) -- The Vatican expressed rare public anger Wednesday in blasting the leaking of private papers from the pope's apartment, a scandal that observers say lifts the lid on a secret power struggle going on behind the closed doors of the Catholic Church.
A top Roman Catholic Church official called the theft of the documents "an immoral act of unprecedented gravity" and "despicable abuse of the relationship of trust that exists between Benedict XVI and those who turn to him."
Archbishop Angelo Becciu made the remarks to the Vatican's official newspaper six days after the pope's butler was arrested for leaking the papers.
Paolo Gabriele, 46, was arrested Wednesday on accusations of illegal possession of confidential documents, the Vatican said in a statement issued three days after the arrest.
With the leaks, the pope's very ministry "has come under attack," Becciu said.
The pope himself referred briefly to the scandal at the end of his regular Wednesday audience, his first public remarks on the matter.
He criticized reports about the affair as "entirely gratuitous" and presenting "a completely unrealistic image of the Holy See."
But experts say that exactly the opposite may be the truth, and that the arrest, alongside the firing of the head of the Vatican Bank a day later, may reveal the battle going on behind the scenes at the Vatican.
The two events are bad PR for the top hierarchy of the Roman Catholic Church, but they may be more than that, experts say. They could affect who becomes the next pope.
The effect of each one is the same: to weaken the authority of Pope Benedict XVI's second in command.
Cardinal Tarcisio Bertone, the Vatican secretary of state, is involved in a power struggle with his predecessor, experts say.
"The reason for this fight is that the secretary of state will have a strong influence over the next conclave which will choose the next pope," said Giacomo Galeazzi, a journalist at the Italian daily La Stampa.
The late John Paul II's secretary of state, Cardinal Angelo Sodano, is trying to sideline Bertone and put one of his own proeteges in place before Benedict dies, Galeazzi said.
"The leaks will end when Bertone is out as secretary of state," he predicted.
He said he expects that Bertone, who will be 78 in December, would be replaced at the end of the year, but not by the cardinal Sodano wants.
Sodano, who is now the dean of the College of Cardinals, isn't the only one who doesn't like Bertone, said the Rev. Thomas Reese, author of "Inside the Vatican."
When he became Vatican Secretary of State, Bertone "did what normally happens. He brought in his team, the people he likes, the people he trusts, and he put them in key positions in the Vatican," Reese said.
"There are people who had hitched their star to the previous secretary of state who thought by now they would become an archbishop or a cardinal, and they didn't," Reese said. "These people are unhappy and don't like Bertone."
Part of the reason for the butler and bank scandals is that the Vatican hasn't been run well in decades, Reese said.
"Clerics don't go to Harvard Business School. Bertone is a theologian. He doesn't have an MBA," he said.
And Benedict is no better, he said.
"He is a German professor. He's a person who is into ideas, not a manager, and yet he is running a 1.2-billion member organization," Reese said.
There's a faction within the Vatican that wants the next pope to be "a better manger who can get the shop in order," Reese said.
"A lot of people think that would be an Italian, of course," after two popes from outside of Italy, John Paul II from Poland and Benedict from Germany, he said.
But the undermining of Bertone may work against that faction, he said.
"Bertone is from the Vatican and is Italian," Reese pointed out. "People may say we need somebody from outside who can come in and knock heads together and make it work."
Reese isn't taking a position on where the next pope should be from, but he has strong views on what Benedict's successor should do: "The place really needs to be restructured and reorganized. It still operates in many ways like a 19th century European court."
CNN's Hada Messia and journalist Livia Borghese contributed to this report.