How JK Rowling freaked Harry Potter fans out with a single tweet

Potter author J.K. Rowling has revealed Harry's son, now the same age as his father in this classic scene, has headed off to Hogwarts.

Every time she tweets, fans freak out - but never like this.

J.K. Rowling, author of the international best-selling series, has created a Twitter storm after revealing that James Sirius Potter, the eldest child of Harry and Ginny, had started school.

I'm in Edinburgh, so could somebody at King's Cross wish James S Potter good luck for me? He's starting at Hogwarts today. #BackToHogwarts

— J.K. Rowling (@jk_rowling) September 1, 2015

Rowling asked anyone going through King's Cross Station, where the magical train portal to Hogwarts is located, if they could wish James good luck for first day.

J.K. Rowling also revealed which house the young Potter had been sorted into. (Photo: Evan Agostini/AP)

She ended it with a hashtag, #BackToHogwarts, which has since gone viral.

It's become one of the top trending hashtags on Twitter, as fans from around the world send their wishes and own regrets about not being there.

@jk_rowling Happy to both wish luck & drive him to school if required - and thank you for inadvertently providing me with my work nickname.

— Driver H. Potter (@DriverPotter) September 1, 2015

Hope everybody made it safely #BackToHogwarts today! Congrats James S. Potter on getting #Gryffindor! Give Neville our love.

— Kennetha Hopkins (@HopkinsKennetha) September 1, 2015

Rowling later tweeted she feared she might be affecting the 11-year-old's first day.

Now worried that he'll be irritated by the number of people saying hi. https://t.co/6keaEOsKS0

— J.K. Rowling (@jk_rowling) September 1, 2015

She continued to tweet about James' first day, revealing he had been sorted into Gryffindor, and that Teddy Lupin, son of Remus, is not happy about it.

Have just heard that James S Potter has been Sorted (to nobody's surprise) into Gryffindor. Teddy Lupin (Head Boy, Hufflepuff) disappointed.

— J.K. Rowling (@jk_rowling) September 1, 2015

This is the latest example of Rowling's prolific Potter tweeting. Since becoming serious over the past year, Rowling has become known for answering fan questions and revealing new information about the series.

This latest Potter-Twitter frenzy will likely be trumped in a few years' time. September 1 2017 is when the 'Nineteen Years Later' epilogue from Deathly Hallows takes place, and many fans are already planning on being there just in case their favourite wizard makes an appearance.

- nzherald.co.nz