The race to be among the first to own a copy of the new Harry Potter book saw more than 30,000 people place orders at Amazon.co.uk in the 24 hours after the announcement of its publication date.

In an effort to grab a share of what is expected to be one of the biggest sellers ever, the internet retailer is offering Harry Potter and the Order of the Phoenix, the fifth instalment in the best selling series, for sale at half its £16.99 cover price - and guaranteeing to deliver it on June 21, the first day it is on release.

The demand for the book, written by JK Rowling, signals a possible repeat of the hysterical scenes in July 2001 when Harry Potter and the Goblet of Fire became the fastest selling book ever.