Police say cashiers need to be on the lookout in Kingsport when handed a $100 bill. Two men have already been arrested for passing the fake bills, and police say the bills are hard to detect. Corporal Detective Frank Light says they believe the bills are being made by bleaching out actual $5 bills, then printing over them. This means the counterfeit detecting pens many cashiers use are not detecting them as fake. Light says the best way to spot the counterfeit money is to hold it up to light and look at both the watermark and the security strip. A true $100 bill will have a watermark of Benjamin Franklin, just like the face on the bill. So if you hold it up and see Abraham Lincoln's face, you've probably got a fake on your hands. Also, a security strip is on each bill that can be seen when held up to the light. If held up and you see the word "FIVE" on a small strip, again it is probably counterfeit. Light also says that if a cashier believes they have been handed a counterfeit bill, hold on to it and do not give it back to the person who gave it to you. Then call the Kingsport Police Department and have them come look at it.