Updated 12.15

The credit card details of up to 500,000 Europeans have been compromised by a data breach at Ennis-based firm Loyaltybuild.

Personal information belonging to over 60,000 Supervalu customers, 8,000 Axa customers and a number of Stena Line customers has been hacked in a "sophisticated criminal attack".

Loyaltybuild - which operates loyalty schemes on behalf of those companies and others - says it has notified gardaí of the breach.

Data Protection Commissioner Billy Hawkes told Newstalk's Pat Kenny show up to 500,000 customers across Europe have had their details compromised:Loyaltybuild says it has been the victim of a "sophisticated criminal attack".

Customers were made aware of a data breach on November 4th, and the Data Protection Commissioner was informed, but it is now clear that the problem is much more serious than first thought.

Fianna Fáil's Michael McGrath says there's really only one option for those hit:

Getaway breaks

The Supervalu customers affected are those who participated in the supermarket's getaway break scheme.

Supervalu says it's suspended the Getaway Breaks booking system pending a thorough investigation and is advising anyone who entered the scheme to watch activity on their bank accounts carefully.

Supervalu is also advising customers to treat with extreme caution any unsolicited communication they received in relation to Supervalu Getaway Breaks.