REPORT: Target Investigating Black Friday Data Breach Involving Customers' Personal Information

REUTERS/Jeff HaynesThanksgiving Day holiday shoppers line up with television sets on discount at the Target retail store in Chicago, Illinois, November 28, 2013.

Target is investigating a possible data breach that could involve of millions of customers' credit and debit card information, journalist Brian Krebs is reporting.

Citing "multiple reliable sources," Krebs says the breach appears to have affected Target stores nationwide and may happened over the course of several days on or around Black Friday.

"The breach window is definitely expanding," a source identified as an anti-fraud analyst at a top-10 U.S. bank card issuer told Krebs. "We can't say for sure that all stores were impacted, but we do see customers all over the U.S. that were victimized."

We've reached out to Target for comment and will update when we hear back.