NEW YORK — Home Depot may be the latest retailer to suffer a credit card data breach.

The Atlanta-based home improvement retailer told The Associated Press Tuesday that it is looking into “unusual activity” and working with both banks and law enforcement.

“Protecting our customers’ information is something we take extremely seriously, and we are aggressively gathering facts at this point while working to protect customers,” said Paula Drake, a spokeswoman at Home Depot, declining to elaborate. She said the retailer would notify customers immediately if it confirms a breach.

Shares of Home Depot fell $1.88, or 2 percent, to close at $91.15.

Many retailers have had security walls broken in recent months, including Target, grocery store chain SuperValu, P.F. Chang’s, and the thrift store operations of Goodwill. The rash of breaches has rattled shoppers’ confidence in the security of their personal data and pushed retailers, banks, and card companies to increase security by speeding the adoption of microchips into U.S. credit and debit cards.

Supports say chip cards are safer because, unlike magnetic strip cards that transfer a credit card number when they are swiped at a point-of-sale terminal, chip cards use a one-time code that moves between the chip and the retailer’s register. The result is a transfer of data that is useless to anyone except the parties involved. Chip cards are also nearly impossible to copy, experts say.

The possible data breach at Home Depot was first reported by Brian Krebs of Krebs on Security, a website that focuses on cybersecurity. Krebs said multiple banks reported “evidence that Home Depot stores may be the source of a massive new batch of stolen credit and debit cards.”

Krebs said that the party responsible for the Home Depot breach may be the same group of Russian and Ukrainian hackers suspected in the Target breach late last year. Krebs broke the news of Target’s breach.

Target Corp., based in Minneapolis, is still trying to get beyond its massive breach that occurred late last year and hurt sales, profits, and its reputation with customers. It has been overhauling its security department and systems and is accelerating its $100 million plan to roll out chip-based credit card technology in all of its nearly 1,800 stores.

New payment terminals will appear in stores by this month, six months ahead of schedule. In April, the retailer announced that it had teamed up with MasterCard to issue branded Target payment cards equipped with chip technology by early 2015.

In its data breach, 40 million credit and debit card accounts were compromised and hackers stole personal information from as many as 70 million customers.

Wal-Mart Stores Inc., the world’s largest retailer, is sending customers who have a store credit card a chip-enabled MasterCard, while its Sam’s Club division introduced a chip-enabled MasterCard in June. The company has chip-enabled check-out terminals in 4,600 stores, and terminals in the remaining U.S stores will be activated before the end of the year.

In a separate statement Tuesday, Goodwill said its customers’ credit and debit card numbers had been stolen at more than 300 stores in 19 states and Washington, D.C., from February 2013 through August 2014. Goodwill blamed the security lapse on an unidentified contractor’s payment processing system. Reports about fraud linked to shoppers’ cards have been “very limited,” Goodwill said.

The company had said in July that it was investigating the breach.

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List of affected Goodwill stores: www.goodwill.org/payment-card-notice

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