F-B-I, Secret Service and local law-enforcement agencies were on the alert this week as merchants discovered cash. Secret Service agent John Gutsmiedl says the fake C-notes have apparently all been spent in the last month. Counterfeit 100-dollar bills started showing up throughout Nebraska and Iowa about three weeks ago, all at merchants close to the Interstate — places where suspects “could get in and out quickly,” he says, and get back on the road. The treasury agent says they’re “fairly” good quality but don’t have the anti-counterfeiting features built into the newest U.S. currency, so if you know what to look for it’s fairly easy to spot them. He says anybody who looks carefully can spot some of the features built into today’s bills to fight counterfeiting. In one corner, the denomination of the bill is printed in color-shifting ink, so if you tilt it the number will appear to change to different colors as the angle changes. Fake money won’t have that feature. The agent says they have some possible leads but he can’t say much as the case is in progress. They’ve found several thousand though he can’t give an exact amount. Gutsmiedl says they’ve been found in “any county along I-80 both in Nebraska and Iowa.” He says a lot of it was spent west of Lincoln in the York area, and more throughout Iowa. The Secret Service, a branch of the U.S. Treasury Department, investigates all cases of counterfeiting.