The police nabbed 110 people around the island for suspected involvement in loan-shark activities over three days last month.
The 80 men and 30 women, aged 18 to 68, were arrested in an operation conducted from Jan 28 to 30.
Officers from the Criminal Investigation Department and seven land divisions conducted simultaneous raids at various locations.
Preliminary investigations showed that 15 suspects may have carried out ATM transfers on behalf of loan sharks.
One other suspect is believed to have provided false contact information in order to obtain loans.
The remaining 94 may have opened bank accounts and given away their ATM cards and personal identification numbers to loan sharks to facilitate unlicensed moneylending businesses.
Opening a bank account, distributing pamphlets, acting as a lookout, being a runner or acting as a harasser for loan sharks are criminal activities that have serious consequences, such as a hefty fine, jail term and even caning, police say.
Under the Moneylenders Act, when a bank account or ATM card of any person is used to facilitate moneylending by an unlicensed moneylender, that person is presumed to have assisted in unlicensed moneylending.
Those convicted of the above for the first time may be fined between $30,000 and $300,000, jailed for up to four years, and get up to six strokes of the cane.
If convicted of acting on behalf of an unlicensed moneylender, committing or attempting to commit acts of harassment, offenders can be jailed for up to five years, fined $5,000 to $50,000 and caned between three and six strokes.
Those convicted of providing false contact information to obtain loans from loan sharks can be jailed for up to 12 months. Under the National Registration Act, a person found guilty of failing to report a change of address can be jailed on conviction for up to five years, fined up to $5,000, or both.
The police also said they had observed a rise in foreign workers borrowing from both licensed and unlicensed moneylenders.
"Employers of foreign workers and maid agencies are urged to engage and remind foreign workers to stay away from loan sharks and not to work with or assist the loan sharks in any way," the police said.
They warned that foreign workers involved in unlicensed moneylending activities will be dealt with firmly under Singapore's laws and have their work passes revoked.
They added that foreign workers who borrow from unlicensed moneylenders may also be barred from working in Singapore.
"The police will continue to take tough enforcement action against those involved in the loan-shark business, regardless of their roles, and they will face the full brunt of the law," the police said.