Several supermarkets across Sweden have reported that their refrigeration and freezer systems were hacked, spoiling food supplies and forcing some stores to close temporarily, public broadcaster SVT reported.
The incident affected several ICA stores, most of them in the southern region of Skane, as well as locations on the island of Oland, in Varmland and Stockholm.
Six Coop stores in the regions of Gastrikland and Halsingland were also hit.
At ICA Nara in Boda, on Oland, store manager Mats Olsson said he arrived to find water covering the floor and a freezer temperature reading of 55 degrees Celsius (131 degrees Fahrenheit).
The refrigeration units had reportedly been switched off, leaving food products spoiled.
At an ICA store in Sankt Olof, manager Dennis Vidal said staff were trying to salvage the situation.
"Right now we are emptying the freezers, there is not much else to do. They are about to get cold again, but everything is ruined," he said.
ICA press officer Gustaf Nilsson said the company was investigating the overnight disruption and assisting affected stores.
"We are aware that a limited number of stores have been affected by an incident during the night that affects their refrigeration and freezing systems," he said.
Nilsson added that the affected stores' connections were outside ICA's central network.
Similar disruptions have also been reported elsewhere in Europe, with dozens of Ahold Delhaize supermarkets in Belgium and Luxembourg affected by an IT incident.
