The author tweeted 'Cry, foe! Run amok! Fa awry! My wand won't tolerate this nonsense,' read her cryptic tweet.
Speculation soon started on sites such as Reddit and Twitter, with many fans noticing that the letters were an anagram of the phrase: 'Harry Returns! Won't say any details now! A week off! No comment,' the Guardian reported.
Rowling fuelled rumors regarding a 'spin-off' of the book, that has the fictional 'magizoologist' Newt Scamander, author of one of Harry's textbooks, Fantastic Beasts and Where to Find Them in the first Potter book.
Reddit and Twitter speculated the news but Rowling said on the micro-blogging site that there would be no more details disclosed and no comments.
Image: JK Rowling. Photograph: Benoit Tessier/Reuters
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