Chocolate bars are being locked in plastic boxes in some UK shops as retailers and police forces warn thieves are stealing them to order.

Sainsbury’s said it had begun using “boxes on products which are regularly targeted”, with £2.60 bars of Cadbury Dairy Milk locked up in one London branch.

Chocolate was more recently being “sold on by criminals and is now being targeted more frequently by prolific offenders,” according to the Association of Convenience Stores (ACS).