Di Rienzo Brothers Bakery in Binghamton has a new check-out tool.

Workers double-check the cash after a few customers passed fake money.

Action News Reporter Julianne Sweeney shows us how businesses and banks can fight this kind of fraud.

The line is long at Di Rienzo Brothers Bakery in Binghamton, and employees exchange money with countless customers.

But last week, there was a bad trade-off.

"They probably watch for the busiest time of the day, and ya know, so they feel like they can just switch it off." says Marilyn Root of
Di Rienzo's.

Di Rienzo's received 2 counterfeit 20 dollar bills.

Root says she suspected something was wrong when she noticed the same exact serial numbers imprinted on both bills.

This is the bakery's second run-in with counterfeit money in a year and a half.

"I guess I've been lucky, ya know, for what little I did get caught." says Tony Di Rienzo.

"To check if money is real or fake...Di Rienzo's is using this counterfeit pen. If you make a mark and it turns yellow like this one, it means the money is real. But if it turns a shade of gray or brown, it means it could be fake." says Action News Reporter Julianne Sweeney.

"We would expect to see them come and then go probably, pretty quickly." says Amy Clark of Visions Federal Credit Union.

Visions Federal Credit Union says counterfeit money pops up sporadically in the area.

In addition to a counterfeit pen, Visions uses a counterfeit detection system.

The machine can detect if a dollar bill is made with authentic ink.

"Be more aware of, ya know, what you're doing and your surroundings because of the fact that you just never know when someone's going to con you." says Root.

"I hope they catch them because it's wrong." says Di Rienzo.

With its own detection system in place, Di Rienzo's says its confident counterfeiters won't burn the bakery again.

As reported Tuesday, Binghamton Police have received 4 or 5 reports of counterfeit money in recent weeks.

The U.S. Secret Service handles counterfeit investigations.