"Scared and, like, nervous. I don't want them to have my information, so I'm going to call the bank bright and early," said Lori Thompson, credit union ATM user.
Police said a review of security footage at the credit union in the 3200-block of Airport Road revealed the device was placed on Sept. 3 by two males, one of whom police described as light skinned and possibly Hispanic, in a white van.
Surveillance video from Sept. 8 showed a light skinned woman with dark hair in a white Chrysler removed the device. Police said the suspects are not known credit union employees.
"Right now we believe that device was on there for about five days, and just think about how many times you personally use the ATM. So I would imagine there's probably at least 20 or 30 a day there, if not more," said Chief Troy Williams, Portage Police Department.
Police said the suspects used the information gathered by the device to make duplicate credit cards, then used them in the area of Hinsdale and Palos Heights in Illinois.
Half a dozen victims have been identified so far, police said, and they expect that number to rise.
"We would encourage these people, if you use that ATM, to check with your credit union. Get a new card, maybe change the account number," Williams said.
Anyone with information about the suspects is urged to call Captain Joe Reynolds at 219-764-5704.
Police said no other banks or credit unions have reported problems, but said it's possible more skimming devices could turn up.
Police reminded customers to check ATMs for damage, scratch marks, and discoloration in the card area and keypad. If something is loose, wiggle or pull on it. If the loose piece comes off, or if something doesn't seem right, don't use the ATM and alert the institution.