WASHINGTON — The FDIC has launched an investigation into questionable financial practices at a local bank, the Chronicle has learned.

The investigation comes after a series of complaints by local residents that the bank, the identity of which has not been disclosed, has undergone several troubling changes over the past few months.

The changes began with the hiring of a new Branch Manager, identified in regulatory documents as Howard M. Mandel. Mr. Mandel’s hiring was followed by a dramatic turnover in bank staff, with most of the bank’s long-time employees replaced by what one federal regulator described as “a parade of pretty girls in short dresses.”

But Mr. Mandel’s makeover allegedly didn’t stop there. He is reported to have renovated the bank interior, replacing a comfortable wood-and-mahogany design with a stark decor of harshly-lit black walls and shiny black floors. Mandel then ordered the removal of the branch’s safety deposit boxes, replacing them instead with a series of individual metal suitcases.

“I used to go into the bank to deposit my paycheck and withdraw a little spending money,” said one local resident, who wished to remain anonymous for fear of a reprisal from bank management. “But the last time I went in, they refused to give me any money unless I played their game.”

This ‘game,’ according to federal investigators familiar with the case, is a pyramid-style scheme in which numerous bank customers place their withdrawal amounts inside the bank’s metal suitcases. Some customers walk away with large sums of money, while others are left with mere pennies.

Although Mr. Mandel is reportedly under suspicion, there is some indication that it is not Mr. Mandel, but a mysterious “banker” who is responsible for the changes at bank.

“We think there’s a shadowy figure who’s really the mastermind in all this,” said one FDIC official familiar with the case, indicating that authorities are monitoring phone calls made from within the bank branch.

Some local residents, however, find the idea that the bank is being investigated laughable.

“I don’t really understand what the fuss is about,” said Darnell Turner, a local restaurateur. “I went in there once, and it seemed like nothing really happened. There was some jumping around, and the girls looked nice, but really it was just a waste of an hour of my life.”

“I just use the ATM now,” Mr. Turner said.