After facing a series of backlash from customers about a children’s coloring book featuring an image of Adolf Hitler, Dutch stores have issued an apology and removed the coloring book from its shelves. Kruidvat, the Dutch drugstore that carries the item posted a statement Wednesday on its website saying they "deeply regretted the incident."

The coloring book titled, Kleuren op Code, showed Hitler giving his signature Nazi Sieg Heil salute wearing a swastika red armband located on his upper left arm. The coloring book, which went on sale Monday, was produced in India, according to the BBC News. It is unknown why the dictator was added in the book. However, the company said they were "investigating exactly how this could have happened."

Read: Adolf Hitler House May Face Takeover By Austria Parliament

"My suspicion is that the man who created the coloring book got a book of famous people out of the closet and selected a pair, which unfortunately included Adolf Hitler. Maybe he did not recognize him," a spokesperson for the Belgian publisher Trifora told Dutch news website NU.nl.

The publisher noted the book also carried historical figures like Nelson Mandela, Albert Einstein and Abraham Lincoln.

"It is a nasty combination of circumstances. We check the book on translations, but do not check all the coloring pictures. We probably should've, but it did not happen," the Trifora spokesperson said. 

Customers can get a full refund once they return the book, the company said, adding the photo was an "inappropriate picture."

A spokesperson for Kruidvat said the book was in the store "for half a day on Monday and several dozen were sold." But they took action once they became aware of customers' complaints.

Yet, after all the complaints that were filed, one Facebook user commented on the company’s Facebook post Wednesday asking for a copy of the book.

"Any chance I still might get a copy of the book?" Damiano Carbone asked.

"We do not sell this book anymore," Kruidvat replied.