PIERRE, S.D. (AP) — Attorney General Marty Jackley is warning South Dakota residents to watch out for unauthorized credit and debit card charges following a potential data breach at Home Depot stores.

Home Depot's outgoing CEO Frank Blake hasn't confirmed that a breach happened. He said Thursday the nation's largest home-improvement chain learned of the possible nationwide data theft Tuesday.

He says Home Depot has hired security firms to help investigate and the company will activate chip-enabled checkout terminals at all of its stores by the end of the year. That technology helps makes transactions more secure.

A cybersecurity website says a "massive" batch of credit and debit cards went on sale on the black market Tuesday and likely came from Home Depot.

Jackley says all consumers should check their bank accounts and free credit report regularly.

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