WAUSAU (WAOW) – Thieves using credit card skimmers have targeted four central Wisconsin cities – Marshfield, Rhinelander, Tomahawk and Wausau.
"Over the past month, we have seen an increasing number of these cases," Marathon County Deputy Sheriff Matt Anderson said.
A skimmer recently was found on an ATM at CoVantage Credit Union in Wausau.
Last week, Marshfield police released photos of suspected thieves installing skimmers at various locations throughout the area, including Simplicity Credit Union and Forward Financial Bank.
Investigators say consumers must be vigilant because some of the skimmers, which steal personal banking information when the card is inserted, are difficult to detect.
"When you go to an ATM or gas pump, jiggle the card holder. If it looks suspicious don’t use it," Anderson said.
Kathy Volkman, a security expert at Cloverbelt Credit Union in Wausau, advises people to keep close tabs on personal information.
"Some of these card readers are internal and not visible on the gas pump or ATM. That’s why you need to be vigilant about the transaction history of your checking account or credit card," she said. "If you do notice something out of the ordinary, contact the issuer of the card immediately. This kind of fraud costs financial institutions big money every year."
Investigators are trying to determine if the skimming cases in the four cities are related.
If you have any information about the thieves call Marathon County Crime Stoppers at 1-877-409-8777. You can remain anonymous and could be eligible for a cash reward.