She’s known for her clever anagrams and word play, so it’s no surprise Harry Potter author J.K. Rowling has used a riddle to announce a new project.

Rowling took to Twitter over the weekend to tell fans she is “working on a new novel”.

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When a fan chimed ion to ask what her new project entailed, the celebrated author couldn’t resist returning to her old ways.

“See, now I’m tempted to post a riddle or an anagram. Must resist temptation… must work …” Rowling wrote, before sending out a quick riddle to her legions of book-hungry fans.

“Cry, foe! Run amok! Fa awry! My wand won’t tolerate this nonsense,” Rowling teased.

The tweet, which has been shared more than 3000 times, has prompted fans to question whether a eighth Harry Potter book may be in the works.

Rowling used word play throughout her popular series of children’s novels, creating the name of evil main character Voldemort from an anagram of his childhood name, Tom Riddle.