(CHICAGO) Customers who used their debit or credit cards at more than 1,000 Wendy’s restaurants nationwide may have had their card information stolen as part of a massive data breach.

The company said the first report of unusual card activity was reported in February of 2016, and may have happened as early as October 2015. Last month, company officials said yet another malware program was discovered in their card processing system and disabled.

Eight Chicago area Wendy’s are among those affected. Those are the restaurants in:

Bradley

Calumet City

Carol Stream

Chicago Heights

Joliet

Kankakee

Mokena

New Lenox

A full list of all the restaurants affected can be found at https://payment.wendys.com/paymentcardcheck.html​.