TWO eight-year-olds who thought they had found a rare Harry Potter book could be disappointed.

Friends Molly Worthington and Eleanor Mason, of Rastrick Preparatory School, thought the Calderdale Council library book could be worth up to £16,000.

Molly had borrowed the book during a school visit to Rastrick Library.

The girls were together when they saw the BBC children's programme Newsround asking youngsters to find 200 missing books.

Children across the country looked to see whether they had one of the valuable first editions of Harry Potter and the Philosopher's Stone.

Newsround told youngsters to check whether their hardback copy may be a collectors' item by looking at numbers printed inside the front cover.

A number printed as 10987654321 shows the book is a valuable first edition.

But the copy found by the girls was printed in 2001 - even though it has the crucial numbers inside.

Head teacher Mrs Susan Vaughey said: "It is a puzzle. I checked and double-checked, and the numbers are clearly there.

"At least the girls have had the fun of looking for the book."