Asda has been fined £300,000 after inspectors found dead mice and flies at a depot that distributes food to online shoppers in London and Essex.
Asda pleaded guilty to three breaches of food safety regulations after an inspection found mouse droppings on shelves and gnawed cereal and sugar packets.
They also found fly pupae shells and rotting coriander in home delivery trays during the visit to the site in Enfield, north London, in May 2016. Asda was also ordered to pay costs of £4,844 to Enfield Council.
Enfield councillor Daniel Anderson, said: "It beggars belief that a national retailer would allow food to be stored in an environment where rodents are running riot.
"It is simply unacceptable for customers to be exposed to the potential risk of harm because a company cannot get its house in order and store foodstuff in a safe and hygienic manner.
"I am therefore pleased that magistrates have taken a tough stance and issued a heavy penalty.
"Hopefully it will send out a strong message to all retailers that we will not tolerate them being less than properly vigilant and ensuring their staff abide by their own stated hygiene policies to protect the health and wellbeing of their customers."
An Asda spokesman said: "The conditions found at our Enfield home shopping centre in May 2016 were completely unacceptable and we are deeply sorry that on this occasion the strict processes we have in place failed at a local level.
"We would like to reassure all our customers that immediate steps were taken as soon as the issue was flagged last year to restore the high standards that our customers expect from us."
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