OKLAHOMA CITY, Oklahoma (KRON/CNN) — Sonic Drive-In was hit by a security breach.

The drive-through chain says it looks like hackers gained access to millions of credit and debit card numbers.

Experts say hackers likely gained remote access to the machines, where you swipe or insert your credit card.

Sonic has 3,500 locations across the United States, but it’s not yet clear how many restaurants or customers may be impacted.

There are four Sonics in the Bay Area–Hayward, American Canyon, Gilroy, and Vacaville.

Sonic says it’s working with police.WHAT OTHERS ARE CLICKING ON:

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