LONDON -- J.K. Rowling004 Archivesrunning out of patience.

The Harry Potterauthor has already described critics of black Hermione as a "bunch of racists" in a recent interview with The Observer. And now she responded to those detractors on her very active Twitter account, because either she loves giving us things to write about or she still needs to learn not to feed the trolls.

SEE ALSO: Emma Watson 'can't wait' to see Noma Dumezweni as Hermione in 'Potter' play

On Thursday evening, someone tweeted at Rowling to describe the casting of Noma Dumezweni in the role of Hermione as "mind boggling".

You May Also Like

10 minutes later, Rowling hit back.

On Friday -- the day after the first preview of Harry Potter and the Cursed Childhad finished -- more people were tweeting at Rowling.

Mashable Trend Report Decode what’s viral, what’s next, and what it all means. Sign up for Mashable’s weekly Trend Report newsletter. By clicking Sign Me Up, you confirm you are 16+ and agree to our Terms of Use and Privacy Policy. Thanks for signing up!

This time, her response was even firmer.

As rightfully dismissive as she's been of these critics, they will probably, sadly return. 

Harry Potter and the Cursed Childopens to the public on 31 July at London's Palace Theatre. The script will be released at the same time, in bookstores and online.

Have something to add to this story? Share it in the comments.