Only the first of four parts of J.K. Rowling‘s “The History of Magic in North America” has been released, but the series is already being blasted for cultural appropriation on social media.

The first installment, released on Pottermore Tuesday, explains the history of wizards and magic in the pre-colonial Americas. It weaves together aspects of Native American culture, such as “skin walkers” and medicine men, with the magical universe of the “Harry Potter” series.

However, some readers online disapproved of what they saw as a “lazy” misrepresentation.

Also read: JK Rowling Explores Pre-Harry Potter Wizards in New 'History of Magic' Story

“You can’t just claim and take a living tradition of a marginalized people,” Adrienne Keene, founder of the website Native Appropriations, wrote on Twitter. “That’s straight up colonialism/appropriation.”

Rowling has not yet responded directly to the criticism, but clarified that her story stands apart from the real life history and culture of Native American peoples.

Also read: J.K. Rowling to Publish Eighth 'Harry Potter' Story This Summer

“In my wizarding world, there were no skin-walkers. The legend was created by No-Majes [the word used in the story to describe non-wizards] to demonise wizards,” she explained to a follower on Twitter asking for clarification on the story’s relation to the real world.

See some of the tweets below:

You can't just claim and take a living tradition of a marginalized people. That's straight up colonialism/appropriation @jk_rowling. — Dr. Adrienne Keene (@NativeApprops) March 8, 2016

You must outta your mind if you think we should sit idly while a renown white author uses us as props in her fictional work. — Native Beauty (@nativebeauties) March 8, 2016

Fuck you, @jk_rowling for appropriation/misrepresentation of Native peoples. https://t.co/EB3vTPmfjD You've added to too high pile of BS. — Debbie Reese (@debreese) March 8, 2016

So this first #MagicInNorthAmerica piece is disappointing because it is so LAZY. — Léonicka (@leonicka) March 8, 2016

Now, there are a lot of invented cultures in the story and that's fine, that's fantasy, but fucking about with an existing culture? — Matt Wallace (@MattFnWallace) March 8, 2016

I'm broken hearted. Jk Rowling, my beliefs are not fantasy. If ever there was a need for diversity in YA lit it is bullish!t like this. — Brian Young (@hungrynavajo) March 8, 2016

And Rowling joins the long, not-so-proud tradition of white women ignoring criticism from Native scholars. — Sarah Hamburg (@sarahrhamburg) March 8, 2016

.@Weasley_dad In my wizarding world, there were no skin-walkers. The legend was created by No-Majes to demonise wizards. — J.K. Rowling (@jk_rowling) March 8, 2016