The problem has now been resolved and the fridges and freezers are working as normal," spokesman Carlos Cancino told AFP.He said Coop did not know who was behind the attack, but noted that the affected stores had been connected to a 4G mobile network, not the updated 5G system, which made them "more exposed" to hackers.Swedish chain Ica also said "a limited number" of its stores experienced refrigeration problems, without confirming a cyberattack.According to Ica spokesperson Helena Johansson, the affected stores were all connected to an external refrigeration control system provided by Danish manufacturer Danfoss; the same supplier targeted in the October 12 cyberattack on French retailers.She referred all queries to Danfoss, which had yet to respond to an AFP request for a comment.In Finland, irregular temperatures were also detected in a few smaller grocery stores belonging to the Kesko group."We are currently investigating the cause, and interference via the network has not yet been ruled out," Petri Kayhko, head of Kesko's corporate security, told AFP.Roni Kokkola, an information security specialist at the National Cyber Security Centre at Finland's Transport and Communications Agency Traficom, would not rule out cyber interference."We've seen this in Europe in the past few months, so it spreading beyond France to other countries has been expected," he told AFP."Nowadays, it's very typical that all kinds of vulnerabilities are being exploited ever more actively and rapidly."In Estonia, at least one supermarket was attacked by hackers who raised the temperature in the refrigeration units to 50C, public broadcaster ERR reported.The units were older models delivered by Danfoss, similar to the ones targeted in the France attack, Jann Mutso, director of Kitman Coldtech, a manufacturer and distributor of advanced refrigeration systems, told ERR.