An investigation into a previously disclosed data breach at Chipotle Mexican Grill Inc. revealed security breakdowns in about 2,250 of its restaurants — including 22 in the Austin metro area.

The company said hackers installed malware "designed to access payment card data" from the restaurants’ registers between March 24 and April 18. The malware could pull cardholder names, card numbers, expiration dates and internal verification codes, the company said.

In Central Texas, the attack affected 15 locations in Austin, two in Round Rock, two in San Marcos and one each in Cedar Park, Georgetown and Pflugerville, according to a special page on the company’s website.

The breaches in the local restaurants began between March 24 and March 27, the company said, and all ended when security was restored April 18.

Customers with questions can visit Chipotle’s website or call 888-738-0534 from 8 a.m. to 8 p.m. Monday through Friday or 8 a.m. to 4 p.m. on the weekend.