TOKYO (AFP) - Kentaro Miura, a Japanese manga author known for his popular dark fantasy Berserk, has died at 54, his publisher announced on Thursday (May 20), prompting an outpouring of grief from fans around the world.

His best-known creation Berserk debuted as a series in 1989 and featured a journey of revenge by a young warrior travelling through a mediaeval-inspired universe.

Praised for its intricate illustrations, it has been cited as an inspiration by numerous authors and creators of comics and video games globally.

Miura died on May 6, Berserk publisher Hakusensha said in a statement.

"All our editors sincerely pray for his repose, expressing our deepest respect and appreciation for his work," the Japanese firm added, noting that his family had already held a private funeral.

News of his death was received with shock by fans.

"I can't even begin to express how devastated I am about the passing of Kentaro Miura," tweeted video game host and interviewer Kelly Link.

"Berserk is an incredible epic that will live for generations as one of the greatest stories ever told, and only to be equally matched by its absolutely breathtaking art."

Canadian art director Pascal Blanche praised Miura in a tweet as "author of one of the best manga" works that have ever existed.

There are currently 40 volumes of Berserk, with more than 50 million copies in circulation in a dozen countries including the United States. The most recent edition was published in Japan in 2018.

It was also adapted into an animated series, a book, animated movies and a video game.

"Miura-sensei was a master artist and storyteller and we had the great privilege of publishing several of his finest works, including his masterpiece Berserk," tweeted American publisher Dark Horse Comics. "He will be greatly missed."