The last book in the Harry Potter series, 'Harry Potter and the Deathly Hallows', has broken pre-order records at bookstore chain Barnes & Noble.

On Thursday, the bookseller announced that it had over 500,000 pre-orders for JK Rowling's latest book, the largest number of pre-orders for any book in its history.

'...Deathly Hallows' is the seventh book in the popular series.

The film of the fifth book, 'Harry Potter and the Order of the Phoenix' is due to be released in July, a week before '...Deathly Hallows' arrives in bookshops around the world.