Hackers forced the temperature of fridges and freezers in many French supermarket fridges up to 50°Celsius (122° F) overnight, causing fires and spoiling food at several hundred stores in a major cyberattack.
The Paris prosecutor's office said a "large-scale" attack was "affecting connected refrigerators in several major food retailers across France", leading to food losses and fires.
Some 150-200 Intermarché shops were targeted in the attack along with almost 100 Coopérative U outlets, the retailers said. Those branches will have to "throw away all of the products" that are fresh and frozen, Intermarché told AFP.
The chief executive of Cooperative U, Dominique Schelcher, described the attack as "unprecedented" and confirmed the cyberattack had affected refrigeration systems since Sunday night.
"Targeting equipment essential to the preservation of fresh products and to the food supply of the French people is extremely serious and is unprecedented. It is unacceptable," he wrote on X.
Carrefour said 80 of its supermarkets had been hit but that the vast majority of its 6,000 stores had not been affected. Around 30 Monoprix were also targeted, the retailer confirmed.
BFM TV reported that hackers "managing to remotely trigger the forced defrosting of the refrigeration systems in numerous stores" of France's largest supermarket chain, E. Leclerc.
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Investigation
The office of the Paris prosecutor confirmed that an investigation has been opened into "the large-scale cyberattack affecting the refrigerators of several major food retail chains across France".
The probe will help "identify the victims and establish the link with the damage they reported in terms of foodstuff losses and the outbreak of fires", the prosecutor's office said.
Intermarché condemned the food waste and financial losses resulting from the attack, without providing figures, and warned there could be issues with insurance policies which do not "cover this type" of in-store incident.
BFM TV said temperatures were "altered remotely, resulting in the destruction of stocks of fresh and frozen products".
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The incident comes against the background of growing concern over the potential havoc that can be caused in Europe in all sectors by cyberattacks by malicious actors.
President Emmanuel Macron, a strong supporter of Ukraine in its fight against the Russian invasion, last month ordered measures to protect France's critical infrastructure from Russian "hybrid attacks".
(FRANCE 24 with AFP)