Hackers raised the temperatures of supermarket refrigeration systems in Germany, Romania and Britain during cyberattacks on Monday, officials said, bringing the number of European countries affected in the hacking spree to at least 11. While Belgium launched a federal investigation, Romania's cybersecurity director described the attacks as "semi-amateur" and ruled out the involvement of state actors. Experts say the attacks took advantage of outdated equipment connected to 4G, prompting retailers such as LoL to rush upgrades to 5G networks and advise disconnecting vulnerable systems from the Internet.