Home-improvement retailer Home Depot officially confirmed a data breach on Monday. Home Depot's investigation is focused on transactions made as far back as April.
There is no evidence that shoppers' debit PIN numbers were compromised, according to a statement the retailer released Monday.
"We apologize for the frustration and anxiety this causes our customers, and I want to thank them for their patience and support as we work through this issue," said Frank Blake, CEO of Home Depot, in the statement.
Analysts warned that the Home Depot breach could rival Target's massive breach last year.
The breach was first reported by security website KrebsOnSecurity almost a week ago. It said the problem could extend back to April and affect all of Home Depot's 2,200 stores in the United States.