GALVESTON, Texas -- Galveston Island is being overwhelmed with fake $100 bills and business owners are being warned to be on the lookout, KPRC Local 2 reported Friday.

Within the past few days, Galveston police have taken reports on six incidents of customers trying to pass fake $100s as the real thing.

"They are wiping off the ink on a $5 bill, and printing the face of a $100 bill on top. Because whoever is doing this is printing the counterfeits on real paper, using the common money marker won't help you," said Capt. Jeffery Heyse.

Debbie Moutz, who manages Hot Bayou on the strand, came face-to-face with a customer trying to give her a fake $100 bill in exchange for merchandise.

"I thought the ink on the bill was a little dark," said Moutz. "So, that tipped me off. Then I held it under the light and saw the faces didn't match up. I was supposed to see Benjamin, but instead I saw Abraham, and then the stripe didn't line up."

Galveston police are investigating each incident, but urge store and restaurant owners to train their employees on how to spot fake bills. Forgery that involves money is a third federal offense and can carry a 2- to 10-year prison sentence.