The boss of a Southend bookshop has defended selling a book which gives details about how to grow cannabis.

Waterstone's in the High Street came under fire for selling "Marijuana - a Grower's Guide" which - although not illegal - is a detailed guide on how to grow marijuana plants, the cultivation of which is against the law.

Now the company's managing director has revealed how the book came to be on the shop's shelves almost by accident after it was ordered by a customer who then cancelled the order.

The revelation comes in a letter to Sir Teddy Taylor, MP for Rochford and Southend East, who was critical of the shop for selling the book.

Waterstone's managing director David Kneale said: "While Waterstone's do not believe in undue censorship of the public's choice of reading material, we obviously do not actually promote books on sensitive subject areas or that are likely to cause offence."

He said that although not a book the shop would normally stock, a copy was ordered originally at a specific customer's request.

"The order was cancelled and the book put on a shelf for returns - where another customer saw and bought it," said Mr Kneale.

"I believe that this is line with our policy of providing a public service within the law, without ourselves giving undue publicity to material which is not of general public interest."

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