Harry Potter author JK Rowling has secretly written a crime novel under a false name.
The Sunday Times reported the writer won plaudits for The Cuckoo's Calling, about a war veteran turned private investigator called Cormoran Strike.
Rowling used the moniker Robert Galbraith for the book, which was published in April, and was only rumbled after the newspaper investigated how a first-time novelist could produce such an assured debut work.
She said: "I had hoped to keep this secret a little longer because being Robert Galbraith has been such a liberating experience.
"It has been wonderful to publish without hype or expectation, and pure pleasure to get feedback under a different name."
According to the Sunday Times, The Cuckoo's Calling has sold 1,500 copies in hardback so far.
Reviewers likened it to works by famous crime writers Ruth Rendell and PD James.
The book was published by Sphere, part of Little, Brown, which published her last novel, The Casual Vacancy.