Local police officers are noticing an uptick in a kind of crime that's as old as money itself — counterfeiting.

Just last weekend, three Carrollton establishments that deal in cash filed police reports with Carrollton Police Department, saying counterfeit bills ranging from $10 to $100 had been passed.

"We've had a real influx of bills lately that are counterfeit," Capt. Chris Dobbs with CPD said. "We encourage store employees to check every bill from $5 to $100."

Dobbs said the following three counterfeit incidents happened last weekend:

• On Saturday afternoon, a person called a hot wings restaurant on Alabama Street, ordering 50 wings.

When the man arrived, Dobbs said he handed what looked like three $10 bills to the cashier, who immediately recognized that they were fake.

When the cashier told the customer that the bills felt fake, the man grabbed the bills and ran out of the store.

Police are attempting to identify the man now.

• Also on Saturday, a counterfeit $20 bill was found in the register at the end of the night when the employees were counting the money.

Since the cashier was not sure when the bill was passed, Dobbs said it would be difficult to ascertain who passed the counterfeit bill.

• On Friday, a woman handed two $100 bills to an employee at the Department of Driver Services in Carrollton.

When alerted by the employee that the bills appeared fake, the woman stayed on the scene until police arrived.

Dobbs said police believe the woman did not know the bills were counterfeit and had legitimate intentions with them.

The captain said local counterfeiters have taken to washing lower-denomination bills and marking them with higher values.

"People will wash the $5 bills to get the number and the president off, and they change it to $100," Dobbs said. "Those washed bills mark good with the pen people use, so you have to hold it up to the light and look for a watermark."

Some bills aren't that convincing — Dobbs said he's seen some that are thick and feel like they're made of plastic. These are the bills that cashiers recognize immediately as being fake, which can lead to grab-and-runs like on Alabama Street on Saturday.

"We don't want the cashiers to put themselves in harm's way, of course," Dobbs said. "The biggest thing is safety — we don't want the cashiers to put themselves in danger for a $10 bill."

The officer said cashiers can be helpful by providing facial or vehicle descriptions for those who grab and run, or even license plate numbers.

"A lot of stores have their own policies, and the employees should follow those procedures, of course," Dobbs said. "Cashiers are usually pretty good about checking the bills they receive, but they have to be more and more careful everyday."

In recent years, advances in computer and photocopy technology have made it possible for people without sophisticated training to copy currency easily.

In response, national bureaus have begun to include more sophisticated anti-counterfeiting systems, such as holograms, multi-colored bills and microprinting.

Software programs such as Adobe Photoshop, once used extensively by counterfeiters, police said, have been modified by their manufacturers to obstruct manipulation of scanned images of banknotes.

Effects counterfeit money have on society, as outlined by police, include a reduction in the value of real money and a decrease in the acceptability of money (businesses may demand electronic transfers of real money).