NEW YORK — A graphic novel for children from the wildly popular “Captain Underpants” series is being pulled from library and book store shelves after its publisher said it “perpetuates passive racism.”

The book under scrutiny is 2010′s “The Adventures of Ook and Gluk” by Dav Pilkey, who has apologized, saying it “contains harmful racial stereotypes” and is “wrong and harmful to my Asian readers.”

The book follows about a pair of friends who travel from 500,001 B.C. to 2222, where they meet a martial arts instructor who teaches them kung fu and they learn principles found in Chinese philosophy.

In a statement, Pilkey said the book "was intended to showcase diversity, equality, and non-violent conflict resolution."

"I hope that you, my readers, will forgive me, and learn from my mistake that even unintentional and passive stereotypes and racism is harmful to everyone. I apologize, and pledge to do better," Pilkey wrote.