If death by chocolate conjures up mouthwatering images of Black Forest gateau, smothered fondant bars or squidgy-centred brownies, be very afraid. There were times when those with a mind to murder made confectionery their weapon of choice.

In the past, unwrapped sweets were often stored in jars and transferred into individual packets or boxes at the point of purchase. With no torn or crumpled wrappers to give the game away, chocolates with creamy centres were relatively easy to tamper with and a determined and dextrous person could introduce poison without leaving obvious signs.