Electronics retailer Dixons Carphone has become the latest victim of a cyber attack - with millions of bank cards and customer data records hacked.
Personal data, such as names, addresses and email details, were accessed by the hackers, Dixons confirmed on Wednesday.
- So how many people have been affected?
Dixons said that the cyber hackers had accessed some 5.9 million customer bank card details.
Around 5.8 million of these were protected by chip and pin, but 105,000 non-EU cards without chip and pin were compromised.
An additional 1.2 million customer records were also obtained, including details such as names and addresses.
- Has any fraud taken place?
Dixons says that, at this stage, there has been no evidence of fraud on the cards as a result of the incident.
The retailer has, however, notified the relevant credit card companies.
Dixons said the hack occurred in one of the processing systems of Currys PC World and Dixons Travel stores.
The data accessed did not contain Pin codes, card verification values (CVV) or any authentication data allowing cardholder identification or a purchase to be made.
- How do I know if I've been affected?
Dixons does not believe that the personal data accessed has left the group's system.
Shortly after the incident, the retailer said it had begun advising customers affected on protective steps they should take.
"We are contacting those whose non-financial personal data was accessed to inform them, to apologise, and to give them advice on any protective steps they should take," a company statement said.
If you need to contact Dixons, you can find out how to do so here.
The Information Commissioner's Office encouraged those concerned about lost data to follow the advice of Action Fraud.
- How has Dixons responded?
Dixons chief executive Alex Baldock apologised over the breach, saying the group had "fallen short".
The retailer has now called in cyber experts and added extra security to its systems, while also alerting the police.
Mr Baldock said: "We are extremely disappointed and sorry for any upset this may cause.
"The protection of our data has to be at the heart of our business, and we've fallen short here.
"We've taken action to close off this unauthorised access and, though we have currently no evidence of fraud as a result of these incidents, we are taking this extremely seriously."