An uptick in reports of fake money have police warning citizens to be careful.

Both the Statesboro and Georgia Southern University police departments reported complaints of counterfeit money in the last few days. Statesboro police reports involved counterfeit bills received at local stores while university police reported that a man complained of being paid in fake cash when he sold a pair of shoes.

“The Statesboro Police Department has seen a slight increase in counterfeit currency incidents during December as compared to the previous months in 2014,” said Statesboro Public Safety Director Wendell Turner in a statement released Tuesday.

The denominations of the counterfeit bills found recently are “predominately twenties,” he said.

“Citizens and businesses are encouraged to be vigilant to ensure that the bills are authentic,” Turner said. “The test pens used by several businesses will often not indicate a counterfeit bill appropriately, so a quick visual inspection will help determine if the bill is authentic.”

While an increase in counterfeit cash spiked recently, overall, counterfeit currency incidents are down for 2014. Statesboro police reported 35 incidents of counterfeit currency in 2012 and 40 in 2013. This year, there have been 13 counterfeit currency incidents so far, according to police records.

Indicators of authentic bills include red and blue fibers in paper, an embedded security strip with appropriate denomination listed and watermarks.

For more information on how to spot counterfeit money, visit http://www.secretservice.gov/know_your_money.shtml.