BOSTON (CBS) - It's the time of the year everyone is shopping, and unfortunately, this is also when more counterfeit money gets passed around.
The U.S Secret Service estimates they took about one million dollars out of circulation in Massachusetts last year.
Counterfeiting is bad news for businesses which have to eat these losses. Honest consumers can also be harmed if they unknowingly get phony bills back as change.
Alaina Conigliaro is accused of passing fake $100 bills at stores along Rt. 6 in Swansea last summer.
"We got scammed," said Jennifer Pacheco. She is the manager at the Dunkin Donuts where Conigliaro allegedly bought gift cards with bogus cash.
Watch: How to spot counterfeit money
The store clerk checked the bill with a special marker and it passed. The bill was actually a $5 bill which had been bleached with chemicals and then reprinted at the higher denomination. "It looked like it", said Pacheco. "But it wasn't, plain and simple."
Later that day, Pacheco put up a sign by the register saying they would no longer accept anything larger than a $20 bill. "Small businesses are taking the hit because they are not getting the money back," added Pacheco.
The I-Team tried to talk to Conigliaro outside Fall River District Court where she is facing charges of counterfeiting. The resident of North Providence, Rhode Island swore at us, threatened to throw hot coffee, and wouldn't answer any questions.
After checking police reports, the I-Team found case after case of counterfeit bills being passed at malls across Massachusetts. At the South Shore Plaza in Braintree, there was one case involving an organized ring trying to pass bad bills at several stores.
In another instance, a teenager was questioned about attempting to use a fake $20 to buy pizza in the food court.
WBZ Security Analyst Ed Davis said, "The people that they catch passing the bills are usually the lowest level people. They are not the ones that manufacture or produce the product."
In recent months, federal officials seized a quarter of a million dollars in Miami. These were counterfeit bills that had originated in Peru.
At JFK Airport in New York, fake $100 bills were concealed in luggage from Ecuador.
Thousands of dollars was even found hidden in children's coloring books being transported from Trinidad and Tobago.
Davis said illegal profits can fuel dangerous international crimes. "Any kind of criminal activity, and terrorism is included, can be funded by these organizations and it is something that really raises the stakes."
The U.S Secret Service is in charge of investigating counterfeit crimes and sees new cases come into their Boston office every day.
A challenge for law enforcement is staying ahead of technology. About 2/3rds of fake bills are now made with laser printers.
Special Agent in Charge Lisa Quinn said shoppers need to be very careful during the holiday season. "If you're the person holding the bill and it's determined to be counterfeit, then you are the one that takes the loss. You're the victim."
Gina Gentilumo, a counterfeit expert with the U.S Secret Service, shared some tips for shoppers so they will be less likely to get stuck with bad cash.
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