Republican presidential candidates Donald Trump and Ben Carson released nonfiction books this year as they hit the campaign trail. But earlier this week, at the Barnes & Noble bookstore in Coral Gables, Florida, the books were shelved in an unconventional location: the "Humor" section.

At the store, Trump's "Crippled America" and Carson's "A More Perfect Union" shared a shelf with a "Hillary Clinton Haiku" book (subtitled "Her Rise to Power, Syllable by Syllable, Pantsuit by Pantsuit") and an Edward Scissorhands "Mad Libs" book.

The misplaced tomes drew immediate conservative attention to Barnes & Noble.

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A Republican Senate staffer noticed the works on the shelf and tweeted about the "liberal bias" of the bookstore:

.@realDonaldTrump and @RealBenCarson in the humor section at Miami Barnes & Noble, clearly no liberal bias @BNBuzz. pic.twitter.com/4686nAi2ag — Robbie Myers (@robbievmyers) December 29, 2015

But as of Thursday, the books have been taken off the "Humor" shelf.

CBS News spoke to a customer service representative at the Coral Gables store who said the books had been removed from the location. The employee, who did not wish to be identified, said that it was "obviously a prank by a customer" and added that none of the Barnes & Noble staff were responsible for filing the books under that section.

Early Tuesday, Carson had responded to the shelving error on Fox News.

"There are a lot of people, particularly on the other side, who really have a very different philosophy of America," the former neurosurgeon, who lives in West Palm Beach, Florida, said. "And people like me are a real threat to them, and people like Donald Trump are a real threat to them."

"But you know, the American people are a lot smarter than these people think," he added. "They're not going to be manipulated as easy as they think they are."