Home Depot is investigating a hack that possibly exposed its customer payment information.
The company on Tuesday confirmed it has partnered with banks and law enforcement to look into "some unusual activity" relating to customers.
Independent cybersecurity journalist Brian Krebs was the first to report this, saying "a massive new batch of stolen credit and debit cards" went for sale Tuesday in the black market online.
In a statement, Home Depot spokeswoman Paula Drake said: "Protecting our customers' information is something we take extremely seriously, and we are aggressively gathering facts at this point while working to protect customers."
The company promised to alert customers as soon as it can ascertain a data breach has occurred.
This could turn out to be another giant hack like the ones that hit several brand name U.S. stores. Since late 2013, the list has gotten extensive: Albertson's, Target, Michaels, Neiman Marcus, P.F. Chang's and SuperValu.
CNN's Devon Sayers contributed to this report.