HARRY Potter author JK Rowling rattled off another 600 book signings in a frantic stop-off on her Hogwarts Express tour yesterday.

About 500 children, parents and teachers waited patiently for the best-selling author, who arrived at Waterstones in Blackett Street, Newcastle amid chaotic scenes.

The millionaire writer is travelling across Britain by steam train as part of a whistle-stop book-signing tour to promote her fourth book in the series, Harry Potter and the Goblet of Fire, which continues to shatter publishing records since its release at midnight on Friday.

Friends Emma Carr and Emily Robson, both ten, from Middlesbrough were dressed as Hermione, the bossy witch in the Harry Potter books.

Emily said: ''It is a fantastic book. I have only read 150 pages so far but I can't wait to finish the rest.''

The author said yesterday that there would be a fifth book but it would not be as long as her latest epic