Hard-up residents in North East Lincolnshire have been warned by trading standards officers to avoid illegal money lenders this Christmas.
A team of investigators has been set up by the council to follow up reports of loan shark activity in the Grimsby, Cleethorpes and Immingham areas.
Officials said research showed that 20% of illegal lending victims took out loans to get extra cash for Christmas.
But failure to meet repayments could lead to harassment, the council said.
Steve Beasant, North East Lincolnshire Council's portfolio holder for community safety, neighbourhoods and customer services, said: Illegal and doorstep lenders often target people who would otherwise be unable to obtain credit from High Street lenders.
"But their interest rates can be extortionately high, and failure to meet repayments can result in much higher financial penalties, harassment for repayments, pressure to take out a bigger loan and the threat of violence.
"We all want to enjoy the festive season, but I would urge local residents to think twice before borrowing money from illegal lenders.
"It might appear that they can get you out of a fix, but you could find yourself in a much bigger financial problem if you're not careful."
He said anyone who had borrowed from an illegal lender or knew someone who had, could get help from the council's illegal money lending team on 0300 555 2222.
The hotline is open across the festive season, answered by trained investigators.
Advice on legitimate borrowing, especially for those who have a poor credit status, is available from Moneyline on 01472 267600 or the North East Lincolnshire Credit Union on 01472 361990.