Arts, crafts and hobby retailer The Works called in cybersecurity experts after its systems were attacked by hackers.
The company, which trades online and in more than 500 stores in the UK and Ireland, said it had closed access to its data internally and externally after being alerted to the unauthorized access by its security firewall.
This had, he said, caused some disruption to deliveries and store functionality, including checkout operations, but these were now beginning to return to normal.
The Works said initial investigations had shown that its customers’ financial details had not been compromised.
“Customers can continue to shop safely at The Works, both in-store and online.
“All debit and credit card payment data is processed securely outside of the group’s systems, through accredited third-party networks and therefore there is no risk that such payment data has been accessed inappropriately,” the statement read.
However, he added that it “has not yet been possible to establish to what extent other data may have been affected”.
The Works said the work of the external forensic cybersecurity experts it appointed was continuing and that it had made “some immediate protective changes to further strengthen its security posture”.
The company said it did not expect the incident to have a material adverse impact on its forecast or financial condition.
Its shares fell more than 10% at the market open.