More than 60,000 Supervalu customers may have had their payment card details compromised.
It emerged last night that a security breach - involving the retailer's Getaway Breaks loyalty programme - is more serious than initially thought.
The retailer says 62,500 customers who booked getaway breaks between January 2011 and February 2012 have been advised to contact their banks and check for suspicious activity on their payment cards.
Supervalu says it's suspended the Getaway Breaks booking system pending a thorough investigation.
Only Supervalu loyalty programme customers who booked Getaway Breaks are affected.