The CEO of Reddit has admitted that he edited comments in a pro-Trump discussion board, saying he “messed with” some of the comments “for about an hour,” and has apologized.

The Reddit users, known as “redditors,” were already seething this week when the site that describes itself as “the front page of the Internet” banned the “Pizzagate” discussion board, where a conspiracy theory was being floated about Hillary Clinton running a pedophilia ring. Pizzagate went down due to a violation of “content policy” after users began posting the personal information of real people who were tied into the theory, like a pizza restaurant owner in Washington, after which they reportedly received death threats.

Reddit, which CEO Steve Huffman describes itself as “the best place online to have truly authentic conversations,” has banned a number of communities in the past. Huffman cautioned last year that it is important to “strike the right balance” in order to keep certain communities from inhibiting some users’ ability to enjoy their time on the website.

But redditors using the popular pro-Trump subreddit called “r/The_Donald” seemed particularly upset with what they viewed as unnecessary censorship, and slung a flurry of disparaging comments in Huffman’s direction. Examples of the insults included “fuck u/spez,” a play off his Reddit username u/spez. Others called him a “cuck,” which is a word, popularized in the alt-right, that accuses one of showing weakness and which has racist undertones.

On Wednesday, one Reddit user provided what purported to be evidence of Huffman editing some of the insults directed at him, by replacing his name with the names of r/The_Donald moderators.

Afterward, Huffman admitted to accusations, expressing remorse for what he did:

Hey Everyone,

Yep. I messed with the “fuck u/spez” comments, replacing “spez” with r/The_Donald mods for about an hour. It’s been a long week here trying to unwind the r/pizzagate stuff. As much as we try to maintain a good relationship with you all, it does get old getting called a pedophile constantly. As the CEO, I shouldn’t play such games, and it’s all fixed now. Our community team is pretty pissed at me, so I most assuredly won’t do this again.

Fuck u/spez.

Despite his promise never to repeat his actions, backlash to Huffman’s admission has ignited further concern about censorship and some are calling for his resignation. This year in particular, with accusations of Facebook of playing favorites with liberal-leaning news stories while supressing conservative news and other sites such as Twitter for suspending the accounts of some alt-right users, many social media users are feeling extra cynical about any moderation performed by site administrators.

After the censorship incident, a leaked private online chat seems to show Reddit moderators in a conversation with Huffman, admonishing the CEO for his actions, but at the same time describing the rowdy r/The_Donald community as a “problem” for which Huffman said his team is looking for “solutions” to deal with.

A former moderator of the r/The_Donald subreddit told the Washington Examiner he believes Huffman should resign.

“I think it would be in the best interest of reddit.com for Huffman to resign from his position as CEO and for the site to focus on hiring a more intellectually diverse and tolerant staff,” the former moderator who used to go by the pseudonym “TehDonald” told the Examiner in an email exchange.

The former r/The_Donald moderator also told the Examiner he has been informed by a friend that due to /u/Spez’s actions, Reddit is no longer protected under Sec. 230 of the Communications Decency Act, which protects publishers from content posted by users on their website. If true, the former moderator said the move demonstrates Huffman’s “utter incompetence.”

Since the editing incident, redditors have continued to rally against Huffman, still calling him a number of names, and some are taking action to have him removed. A Change.org petition has been launched asking for Huffman to resign, and has more than 4,000 signatures.

The backlash isn’t unprecedented. Last year, more than 200,000 people called for interim Reddit CEO Ellen Pao’s resignation because of controversies over censorship in the Reddit community.