Check your pockets because there is a chance you could be holding a counterfeit bill. The U.S. Secret Service's field office in Minneapolis says the amount of fake currency they've collected in Minnesota this December nearly doubled compared to the same month a year ago.
"We see a lot of people -- gang activity -- with counterfeit, people involved in the drug trade," said Special Agent in Charge Louis Stephens. "With the advent of accessible and cheap computer technology and high-end scanning and copying technology, it's much easier to counterfeit money now then it was 20 years ago."
Stephens says the easiest ways to detect a fake are to:
Look for color changing ink on the number at the bottom right.
Hold the bill up to light and look for the watermark and vertical, embedded fiber.
According to Stephens, about $300,000 worth of fake currency was passed around Minnesota in 2012, 22 percent around the holidays in December and January.
"The last person holding it takes the loss, so it really pays to examine your currency before you accept it," said Stephens.
Twenty dollar bills are copied the most often, but investigators have also seen singles.
"You probably have but never knew it," Stephens said. "Americans generally are not very good at knowing if the currency we have in our hands is real or not."
For information about how to check the currency in your wallet, click here.