Banca Monte dei Paschi di Siena (MPS), Italy’s third-largest bank and the world’s oldest, has admitted in a statement posted quietly on its website that its customer deposits have fallen by a “few billion euros.”

That was after a series of scandals rocked the more than 600-year-old institution, which included a €730 million derivatives loss it racked up from 2006 to 2009.

These transactions are at the heart of a fraud probe at the bank. Italian prosecutors are investigating whether MPS used derivatives transactions to hide losses from regulators.

Bloomberg reported in January that Deutsche Bank designed a derivative for MPS in 2008 that obscured the Italian bank’s true financial position just before it applied for a taxpayer bailout. MPS reportedly engaged insimilar trades with Nomura, and Italian police recently searched the Japanese bank’s Milan office.

MPS’ troubles appear to have started in 2007, when it overpaid to buy smaller rival Antonveneta without doing any due diligence.

The bank’s former finance chief, Gianluca Baldassarri, has been jailed, accused of misleading Italian regulators over the derivatives trades.

And in a mysterious twist, MPS head of communications David Rossi was found dead at the bank’s headquarters in early March, reportedly after feeling pressured by the fraud investigation, although he was not himself a subject of the probe.

Unsurprisingly, MPS has issued terrible financial results for 2012, posting a €3.2 billion loss. largely due to bad debt provisions and losses on its derivatives trades. The bank released these results at 5.45 p.m. on Maundy Thursday, when many of its Italian depositors and shareholders would have already gone home from work to start their Easter holidays.

The MPS scandal has raised questions over the Italian government’s oversight of its financial institutions. Italy agreed to bail out Banca MPS back in June 2012. On Jan. 26 it agreed to extend another €3.9 billion to the poorly funded bank, including rolling over a €1.9 billion loan the bank took out in the middle of the financial crisis.

The affair also contributed to the chaos that is still raging over Italy’s recent general elections. MPS had deep links to Italy’s center-left Democratic Party, which had been tipped to win in the February poll, but failed to secure a majority in the Senate necessary to take control. Italy still does not have a government.