(CBS News) LONDON - A scandal that has rocked Vatican City threatened to expand Monday. So far, the only person under arrest is Pope Benedict XVI's butler. But few believe that he is the sole source of the leaks that have exposed corruption and double-dealing inside the leadership of the Catholic Church.
At the center of the holy whodunit is Paolo Gabriele, the pope's personal butler. Since he was arrested last week on suspicion of stealing confidential documents, rumors have swirled that he must have had some high-ranking help -- perhaps as high as the so-called 'princes of the Church,' the cardinals.
Marco Tosatti covers the Vatican for one of Italy's biggest newspapers. "If Paolo Gabriele acted as he did," he said, "well, probably there was somebody very important who convinced him to do it."
On Monday, the Vatican denied that any cardinal was under investigation.
But the scandal shows no sign of slowing. The butler pledged that he'd cooperate fully with investigators, raising the specter that he would name others.
Gabriele -- a father of three -- has worked for the Pope since 2006, and is one of the few layman to have access to the Pope's private apartment.
He's accused of leaking letters and memos to Italian journalists that allegedly show corruption in the Church's financial dealings with Italian businesses, including money laundering and kickbacks.
The revelations are part of a number of embarrassing leaks that show the Church and its inner workings in disarray.
For the moment Paolo Gabriele is the lone arrest. If found guilty, he could face up to 30 years in prison.