Supermarket freezers and fridges across seven European countries were hit by a cyber-attack, according to the BBC. Around 40 Delhaize supermarkets in Belgium and Luxembourg were affected, along with a smaller number of shops in Sweden, Ireland, the Netherlands, Estonia and Finland.

Sabcobel, a Belgian company that manufactures some of the affected refrigerators, said the units' evaporators were switched to defrost mode, causing them to warm up. The company said this method is believed to be the same one used in last month's incident, which hit hundreds of French supermarkets. Stephan Moelans, Sabcobel's CEO, told the Belga news agency that the incident was a cyber-attack. He said the company had been "working all night and morning to disconnect the affected units from the network."

Moelans said the company had been working since the French attack in early October to "protect our customers fridges against this vulnerability," but that the units needed physical modifications, not just software updates.

The temperature of freezers in several shops reportedly rose as high as 50C (122F). The BBC reports that it is unclear who is behind the attack.

Belgium and Sweden's national cyber-security agencies said they are monitoring the incident. The UK's National Cyber Security Centre said it is working with international partners and industry to "fully understand details of an incident." No incidents have been reported in the UK.

A Delhaize branch in Hoeilaart told Het Laatste Nieuws that it had lost €100,000 worth of produce. Carrefour said 15 of its Belgian stores were affected. Colruyt Group, which operates Spar stores in Belgium, said five shops had their fridge systems attacked. Ikea said its Mons store in Belgium was affected, and a spokesman said "we cannot rule out that additional locations may be affected."

In Sweden, a spokesperson for ICA confirmed that a "small number of ICA stores operating outside ICA's central network" were affected. Seven of Coop's 800 stores were also hit, the company told the BBC, adding that the "situation is currently contained and under control."

In Finland, the owner of the Kesko supermarket chain told Helsingin Sanomat that its security experts were investigating the cause of refrigerator malfunctions at some K-stores. In Ireland, a spokesman for Musgrave Group confirmed to The Irish Times that a "cyber incident" affected refrigeration systems at 13 SuperValu supermarkets, but said the impact was limited to a "specific model" of refrigerator. A Danfoss spokesperson told NOS that the freezing and cooling systems of at least 17 companies in the Netherlands were attacked overnight. A Selver supermarket in Estonia was also affected, according to ERR.