Federal agents say that counterfeit $100 bills are popping up at stores across the metro area, with crooks even passing a bogus bill to a Boy Scout troop selling Christmas Trees in Independence.

Workers at Boy Scout Troop 492's Christmas Tree lot in Independence say that they have had trees stolen in previous years, but they had never lost as much as $100 until now.

"(The suspect) went inside and paid her with that $100 bill, and she didn't notice it," said Troop 492 scoutmaster Gene Pittman. "Then when he come out, he was high-stepping it back to their truck, well he forgot his Christmas tree. So here I grabbed it and went running and said 'Hey wait a minute you forgot your Christmas tree.' He took it by the tip and threw it in the back of the pickup. I should have known something was funny there."

Pittman says that the Christmas tree sale helps fund their summer camping trip to South Dakota.

The $100 bill that the scouts had been given was actually a $5 bill that had been "washed" clean and reprinted in the higher denomination, according to the U.S. Secret Service, who says that 13 of the phony bills have been passed to merchants in the Village West area of Kansas City, Kansas, since October.

"We don't believe this is one group working this," said Chuck Green of the U.S. Secret Service. "People have known about bleaching money for a long, long time. It's a lot of work. There are a lot of things involved in it. Trying to print the image back onto that little square paper, it's very difficult to get it lined up and printed properly. We don't see it all that often."

By using actual U.S. currency paper, a counterfeit detection pen merchants often use will not identify the "washed" bills as fakes. But if you hold the bill up to the light, a watermark of Abraham Lincoln, instead of Benjamin Franklin, will give the bogus bill away.

The Secret Service says if you unknowingly get one of these bills, it is illegal to pass it along to the next guy. Instead, you should call your local law enforcement agency as soon as possible.