British meat suppliers and supermarkets in seven European countries were forced to throw out their supplies after a suspected cyber attack .

Fridges and freezers have been hacked with thermostats remotely cranked up in some cases to 50C (122F), while others have been set to “defrost” mode putting the heat to 15C rather than minus 22C.

Hundreds of shops were targeted by the overnight cyber attack, which caused millions of Euros worth of fresh and frozen food to be spoiled.

The UK National Cyber Security Centre has warned British retailers to urgently update the software on fridge temperature controllers adding that the attack is a “wake-up call” and our “digital infrastructure remains outdated and vulnerable”.

Here, the Independent breaks down how an attack like this is possible and if the UK is under threat of more attacks.

Employees empty freezers to load shopping carts with frozen goods that have to be thrown away at ICA Kvantum supermarket in Sjoebo, Sweden (AFP/Getty)

Which supermarkets were…