Supplies of Walkers crisps have been disrupted by an IT upgrade. The Leicester-based crisp giant confirmed products including multipacks of ready salted, Quavers and Wotsits had been affected. A number of these are currently unavailable on the Tesco website and there are reports of empty shelves in some shops. A spokeswoman said the firm was "working round the clock" to increase the supply to stores across the UK. She added: "We are currently experiencing disruption to the supply of some of our Walkers snacks products, as a result of a recent IT system upgrade. "We're very sorry for the inconvenience. "We're incredibly grateful to all our colleagues in Leicester and our other sites for their hard work and dedication as we work through this issue." Hoarders however are cashing in on the lack of the availability of the crisps and selling packets online, some for up to £8.