During the cyber attack, the cooperative narrowly avoided lockdown of its computer systems that left customer data stolen and store shelves exposed, and the hacker claiming responsibility told the BBC.

The revelation can help explain why the co-ops recover faster than other retailers M&S, whose systems are more comprehensively damaged and still fail to perform online orders.

The hackers responsible for the two attacks told the BBC that they tried to infect the cooperative with a malware called Ransomware - but failed when the company discovered the attack in the operation.

Both the Co-op and M&S declined to comment.

The gang used the cybercrime service Dragonforce to launch a long and aggressive sensation against the BBC.

"The cooperative's network has never suffered from ransomware losses. They pulled up their own plugs - sales, burn logistics and smudge shareholders' value," the criminal said.

But network experts like Jen Ellis, the ransomware task force, said the cooperative's response was wise.

"The cooperative seems to have chosen self-imposed immediate destruction to avoid crime, long-term destruction. In this case, it seems to be a good appeal for them."

Ms Ellis said these crisis decisions are usually made quickly when hackers violate the network and can be very difficult.

The criminals exclusively told the BBC that they claimed to have violated their computer systems before they were discovered.

They boasted, “We sat in their network for a while.”

They stole a large amount of private customer data and planned to infect the company with ransomware, but were found.

Ransomware is an attack in which hackers compete for computer systems and ask victims to pay in exchange for a return of control.

This will also make the recovery of the cooperative system more complex, time-consuming and expensive - it is M&S that seems to be fighting against.

The criminals claimed they were also behind the M&S attack on the Easter attack.

Although M&S has not confirmed it is dealing with ransomware, network experts have long said that in this case, M&S has not suggested any suggestions or corrections to the contrary.

Retailers are still working to get back to normal after nearly three weeks as online orders are still suspended and some stores continue to have problems on contactless payments and empty shelves this week.

An analysis by Bank of America estimates that the consequences of hackers cost £43 million per week.

On Tuesday, M&S admitted that personal customer data had been stolen, which could include phone numbers, home address and date of birth.

It adds data theft does not include available payment or card details, or any account passwords - but customers are still urged to use that information to reset their account details and stay alert to potential scammers.

The co-op appears to be recovering faster, saying its shelves will return to normal starting this weekend.

Nevertheless, the impact of the cyber attack is expected to be felt for some time.

Professor Oli Buckley, a cybersecurity expert at Ruffborough University, told the BBC: “The cooperatives are moving quickly, and their work on recovery helps to soften slightly, but the work of rebuilding trust is much harder.”

"This will be a further process that shows that the course has been studied and that there is a stronger defensive ability," he added.

The same cybercrime group also claimed responsibility for attempted hacking by London department store Harrods.

Hackers who contacted the BBC said they are from Dragonforce, which runs a member cybercrime service so anyone can use its malware and website for attacks and ransomware.

It's not known who ends up using the service to attack retailers, but some security experts say the strategy seen is similar to a loosely coordinated group of hackers known as scattered spiders or eighty-year-old orgy.

The gang operates on Telegram and Discord channels, speaks English and young – in some cases only teenagers.

The conversation with the partner hacker was conducted in text form - but it was obvious that the hacker, who called himself a spokesperson, was a fluent English speaker.

They said two of the hackers wanted to be called "Raymond Reddington" and "Dembé Zuma," a character in the blacklist of American crime thriller involving a wanted criminal who helped police remove other criminals from the "blacklist."

"We are blacklisting British retailers", the hacker said.