Children's clothing retailer Mothercare is the latest company to have been affected by the security breach at email marketing service provider Epsilon Interactive.
Marks and Spencer was revealed to have been affected by the breach earlier this week, with both companies among approximately 50 brands worldwide that have been hit.
Epsilon first warned of the incident last Friday, saying that someone had got into company systems and obtained e-mail addresses and names belonging to some of its customers. It said that around 2 percent of its 2,500 clients were at risk, and the list of companies includes Barclays Bank, Citibank, Hilton Worldwide and Marriott International.
In an email to customers, Mothercare said that names and email addresses had been stolen in the breach.
The company wrote: "The most likely impact, if any, could be a receipt of spam emails. As a precaution we would like to remind you to only open emails from senders you know and not to share personal information via email.
"We apologise for any inconvenience this may cause you. We take your privacy very seriously and we will continue to work to ensure that all appropriate measures are taken to protect your personal information from unauthorised access," it added.