The Southern Poverty Law Center apologized on Wednesday to Ben Carson after placing the potential Republican presidential candidate on its "Extremist Watch List" -- which is mostly made up of hate groups and white supremacists.

Carson was placed on the list last October by the civil rights advocacy group for allegedly being "anti-gay." The group drew criticism after the listing was reported on last week

"In October 2014, we posted an 'Extremist File' of Dr. Ben Carson," SPLC wrote on its website. "This week, as we've come under intense criticism for doing so, we've reviewed our profile and have concluded that it did not meet our standards, so we have taken it down and apologize to Dr. Carson for having posted it."

Among the reasons the SPLC gave for initially putting Carson on the list includes a March 26, 2013 interview on Fox News' "Hannity."

In that interview, Carson said, "Marriage is between a man and a woman. It's a well-established pillar of society and no group, be they gays, be they NAMBLA [North American Man/Boy Love Association], be they people who believe in bestiality -- it doesn't matter what they are, they don't get to change the definition."

The SPLC also took Carson to task for similar remarks made to "The Baltimore Sun" on March 29, 2013 as well as in his book, "America the Beautiful," where he linked redefining marriage based on societal pressures to the "dramatic fall of the Roman Empire."

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Though the SPLC apologized for putting Carson on the list, it maintains Carson has "made a number of statements that express views that we believe most people would conclude are extreme" and said "we believe that his views should be closely examined."

Other "featured" extremists on the SPLC's list include Craig Cobb, who is best known for his botched effort to turn Leith, N.D., into an Aryan stronghold and Harry Cooper, the founder of Sharkhunters International, a company that organizes tours to places like Adolf Hitler's vacation home in Bavaria.

Carson, a neurosurgeon and vocal Obama critic who is popular among conservative groups across the country, is currently the only high-profile black candidate considering a White House bid. He has not made a formal announcement about his 2016 plans.