There’s a lot of counterfeit money changing hands in Conway in the last few days, and merchants and shoppers are urged to take a close look at their bills.

So far, the counterfeit bills have been passed — sometimes successfully — at local McDonald’s, Bear’s Den, Domino’s and Fu Lin restaurants, at a Murphy Oil gas station and at Conway Corp. A woman got a fake $20 with her change from the Salem Road Kroger on Monday (the manager checked the money in the register and gave her a real $20 when she came back), and a German Town Apartments maintenance worker found several fake $20s outside an apartment, some of which hadn’t been cut out of the sheet they were printed on.

$20, $50 and $100 bills have been collected as evidence.

Real money is printed on paper made from cotton and linen, unlike office paper that is made from plant cellulose. The types of paper "feel" different, and markers used to detect a fake bill use ink that chemically reacts with cellulose but not cotton or linen.

Some of the counterfeit money going around is printed on regular cellulose paper, Det. Brian Williams said, and it’s fairly easy to tell these by feel. But some are made by bleaching $1 or $5 bills and printing $50s or $100s on them. These will pass the marker test, "but they don’t look as good as genuine currency and you’ll probably still see some ink from the $5," Williams said.

Also, two counterfeit $100s collected by CPD have "For Motion Picture Use Only" printed on them and without the language "Federal Reserve Note." This is "prop money," which can legally be bought online. In addition to bearing language saying it's for movies or "not legal tender," prop money isn't — and legally can't — be an actual copy of genuine bills. The artists who design a prop $100, for example, draw their own Ben Franklin (with varying success) and might draw different buildings on the notes.

The descriptions of the suspects who have passed, or tried to pass, counterfeit bills vary. They have been males and females of several ethnicities, Williams said.

The U.S. Secret Service investigates counterfeit currency claims, and "they’ve been made aware of the magnitude of the problem here," Williams added. "The main thing is to know it’s out there and for business owners to tell their employees that it’s out there."