M&S disclosed that it was dealing with a ‘cyber incident’ on 21 April and has since suspended online ordering, while the attack on the UK Coop appeared to come a few days later.
Criminal hackers known as DragonForce claiming they had stolen the private information of 20 million people signed up to the Coop’s membership scheme.
It is unclear if M&S has been targeted by the same group, or what demands or threats have been made to either company.
The Channel Islands Coop said that the data of its members had not been compromised as the attack had not impacted its own data security or systems functionality.
‘Coop Group does not store names, addresses or personal details relating to members of the Channel Islands Coop,’ a spokesman said.
‘The systems and data of the Channel Islands Cooperative Society remain secure, and there has been no compromise to member information.’
He said that all of the society’s stores across the islands remained open and trading.
The society was ‘working around the clock’ to reduce disruption and return to full product availability as soon as possible.
‘However, due to the sustained malicious attempts by hackers to access to Coop Group systems, they have taken proactive steps to keep their systems safe, which is temporarily impacting our colleagues’ ability to perform their roles, and how many deliveries we are getting into our stores.’
The three M&S stores in Guernsey are run by Creaseys.
A spokeswoman for M&S said as part of its proactive management of the incident, it had taken a decision to take some of its systems temporarily offline.
‘As a result, we currently have pockets of limited availability in some stores,’ she said.
‘We are working hard to get availability back to normal across the estate.’
Visits to M&S at L’Islet and the Coop supermarket on the Bridge yesterday showed that only limited products had been affected, mostly fresh products such as fruit and chilled meats.
Signs on empty shelves at Coop apologised to customers for the inconvenience caused.
Sarah de Carteret from local retail bloggers Supersavvysavers said she had not yet seen much difference in stock levels at either store.
‘I do my top-up shops at the Coop and have seen no change’, she said.
‘None of our followers have brought shortages up at all, so it does not seem to be much of a problem so far.’
Coop stores across the Channel Islands have been affected but is unclear if M&S in Jersey was also encountering issues.
Jersey Consumer Council chairman Carl Walker said his organisation was aware of the issues at Coop but was still trying to establish if M&S was affected.
‘At Coop it appears deliveries are being impacted,’ he said.
‘It indicates they have having issues with their booking and ordering systems. Consumers will just have to be patient while the stores sort it out.’
You need to be logged in to comment. If you had an account on our previous site, you can migrate your old account and comment profile to this site by visiting this page and entering the email address for your old account. We'll then send you an email with a link to follow to complete the process.