Located in Kamathipura, Mumbai's red light district, the bank was started by a handful of sex workers driven by a desire to save for a time when their bodies stop earning.

With most of them without birth certificates or residence documents, prostitutes rarely are able to open accounts in regular banks or obtain credit.

But for two months now, Gangubai has been fulfilling a dream by squireling away about a dollar a day in Sangini Women's Co-operative Society bank, savings

that had so often been snatched away by drunken pimps and local toughs.

"I'm getting old but I can still save to build a house in our village," the middle-aged prostitute said, her face heavily daubed in cheap cosmetics.

"I once tried to open an account in a bank, but they drove me away once they knew my profession."

Although prostitution is illegal in India, it is a thriving underground industry and voluntary groups estimate that there are about 2 million women sex workers, most of them trafficked or forced into the work by crippling poverty.

With most of their lives spent repaying the investment of the brothel owners, sex workers find it almost impossible to break away from the cycle of poverty and exploitation, and often turn to private moneylenders who charge exorbitant interest rates.

Most of the new bank's customers say they are saving to build houses in their hometowns and villages. Many others say the money would help them send their children to good schools.

Such is the response that within months of the bank's startup, capital has grown steadily and the amount remains invested in fixed savings schemes.

Earnings from the fund goes partly towards paying savings interest to about 1,000 of the bank's customers and the rest is used to pay salaries and give loans.

With some surplus cash, the bank, functioning out of three tiny rooms with the help of Population Services International (PSI), a Washington-based NGO, has even started a subsidised grocery store for Kamathipura's estimated 22,000 sex workers.

Shilpa Merchant, the Mumbai head of PSI, which helped with the startup capital, says the bank has begun changing the financial outlook of sex workers.

For instance, Yamna Mettgud says she is saving to buy a car to rent out. "I want a steady income from the business when I am done with this," the 40-year-old, mother-of-two said.