In an update issued on Friday, the Co-op confirmed that ongoing forensic investigations into its cyber attack had revealed that the hackers were able to gain access – and extract data from – from one of its systems.

“The accessed data included information relating to a significant number of our current and past members,” a spokesperson for the Co-op said.

In a message to its members, Co-op CEO, Shirine Khoury-Haq, confirmed the cyber incident had compromised customer data, saying a “limited amount of member data, which included name, date of birth and contact details” had been accessed.

She went on to say that the cyber criminals had not been able to access the financial information of any members, apologising for the incident and urging customers to take the usual precautions of keeping passwords safe and protected.

She went on to say that the Co-op had, so far, been able to protect itself from significant trading disruption, but acknowledged the concern the breach of customer data will have posed.

Last week, Harrods became the latest retailer to become embroiled in a cyber incident. Meanwhile disruption at M&S – including the suspension of online orders and freezing digital recruitment – following a hack over the Easter weekend remains ongoing. Speaking to The Guardian, some industry insiders suggested it could be weeks before the retailer’s website is back to full operations, and even months before all systems are back up and running.