Police in central Illinois have announced instances in which high-quality counterfeit $100 bills have surfaced.

Reports state that Lincoln police said this week there are two locations in the city where $100 bills were passed. The money appeared real even after clerks used counterfeit marking pens to check them.

Lincoln police urge businesses to follow appropriate procedures to identify money.

Joe Roesch is chief deputy of the Sangamon County Sheriff's Department. He says between Dec. 15 and 17, a man went into businesses on Springfield's north side and asked for change for $100 bills. In one case, the man convinced a customer to break the bill for him when the store didn't have change.

The U.S. Secret Service is responsible for investigating counterfeit money.