Harry Potter fans are in for as treat, with author JK Rowling announcing she is to release three new Hogwarts-themed books in September.

The three titles in the Pottermore Presents range intend to bring together new stories and first-person reflections on the wizarding world, as well as writings already published on the Pottermore website (an information and articles site about the fictional world).

Short Stories From Hogwarts: Power, Politics And Pesky Poltergeists offers "a glimpse into the darker side of the wizarding world, revealing more about infamous teachers such as Professor Umbridge, Horace Slughorn, and Quirinus Quirrell. It also seeks to offer the lowdown on the Ministers for Magic and the history of the wizarding prison Azkaban.

Characters such as Professors Minerva McGonagall and Remus Lupin, will be profiled in Short Stories From Hogwarts: Heroism, Hardship And Dangerous Hobbies, including information on Professor McGonagall's role in the second wizarding war.

The third tome Hogwarts: An Incomplete And Unreliable Guide intends to "bring the school of witchcraft and wizardry alive".

Pottermore CEO Susan L Jurevics said the e-books will "supplement the Harry Potter book series" and are easily able to be read in an hour.