Supermarket fridges and freezers in at least 11 European countries and the UK  have allegedly been hacked, and in some cases had their thermostats remotely turned up to 50 degrees.

According to The Guardian, the EU has condemned the act, which they described as a deliberate attempt to disrupt the food supply chain and undermine consumers’ confidence in it.

Al Jazeera reported earlier this week hackers raised the temperature of refrigeration systems at supermarkets in Germany, Romania, Belgium, Estonia, Finland, Ireland, Italy, Luxembourg, The Netherlands, Portugal, and Sweden, however the motive behind the cyberattacks is unknown and no one has claimed responsibility.

Thomas Regnier, a spokesperson for the EU, said the bloc’s agencies were talking with national authorities to develop a joint response.

“These are not isolated incidents, and of course, we have to be collectively resilient and prepares for such cyber incidents,” he said according to Al Jazeera.

However, Romania’s top cybersecurity expert, Dan Cimpean, has played down the event.

“It seems semi-amateurish,” he said to AFP News Agency.

“We do not suspect, under any circumstances, that it is a state actor.”

Belgium was the hardest hit, with dozens of stores across multiple grocery chains reporting refrigeration failures, while 20 supermarkets in Italy were affects. In the UK, the hackers allegedly tried to target small meat processing firms with limited success. In Sweden it was fridges and freezers within several Coop supermarket stores that had been affected, each of which had been connected to old 4G networks.

Coop spokesperson Carlos Cancinos said the company had accelerated an upgrade to connect refrigeration equipment onto 5G and modern modems.

“This helps to solve a large share of problems of this kind,” he said.

Cybersecurity  expert Frank Groenewegen, who works at Deloitte in The Hague, has urged retailers to check whether their refrigeration controllers were connected to the internet and running the latest security updates.

“And if they don’t even know, they remove them from the public internet immediately,” he told Reuters.

“With disconnecting, you haven’t fixed the root cause but you’ve at least isolated those systems to that an attacker is not able to do this.”