Hy-Vee Inc. security officials are working with Altoona, West Des Moines and Des Moines police departments to investigate three separate incidents of a skimmer, a device used to obtain debit card information, being found on ATMs at Hy-Vee stores. The first skimmer was discovered Saturday evening at the Altoona Hy-Vee, 108 Eighth St. S.W., after a customer reported problems using the ATM and noticed a device on the machine that looked suspicious. Late Saturday night, two other skimmers were discovered: one on an ATM inside the Valley West Hy-Vee, located at 1700 Valley West Drive in West Des Moines, and the other on an ATM inside the Southridge Hy-Vee, located at 1107 E. Army Post Road in Des Moines. The incidents are currently under investigation by the Altoona, West Des Moines and Des Moines police departments. Hy-Vee said that it is working to notify all customers who made a transaction at the three ATMs, and that all the ATMs at Hy-Vee stores in the Des Moines area have been inspected and no additional skimmers have been found.