Over 10 million Japanese versions of the immensely popular "Harry Potter" book series have been published in Japan, a Japanese publishing company said Tuesday.

Say-Zan-Sha Publications Ltd. said the company has published 4.46 million editions of "Harry Potter and the Philosopher's Stone" since December 1999, 3.23 million of the second book, "Harry Potter and the Chamber of Secrets," and 2.7 million editions of the third installment, "Harry Potter and the Prisoner of Azkaban."

The books, authored by J.K. Rowling, follow the adventures of a young wizard. They have been global best sellers since the first book hit the stands in 1997 in Britain.

The film version of "Harry Potter and the Philosopher's Stone" has also become an international box-office hit.