The apology only came after CNN identified and contacted the man.

In case you missed it/blocked it out, President Trump on Sunday tweeted this video of himself beating up "CNN" during a wrestling match. #FraudNewsCNN #FNN

The clip is originally from a 2007 appearance Trump made on WWE's WrestleMania in which he tussled with wrestling CEO Vince McMahon. (Fun fact: Linda McMahon, Vince's wife, is now the small-business administrator in Trump's cabinet. Good times.) Trump's been feuding with the media a lot in recent days, but he has been particularly obsessed with CNN following the network's retraction of a story on Russia. The network denounced Trump's tweet, saying it encouraged violence against reporters.

The wrestling video was originally lifted from a post on Reddit for Trump's fans. The clip, which had no sound in the Reddit version, was posted by a user named “HanAssholeSolo.” Reddit

"Congratulations /u/HanAssholeSolo, your dankery has been tweeted by the President of the United States," a fellow redditor commented on the post after Sunday's tweet.

Then writer and Georgia Southern University assistant professor Jared Yates Sexton began tweeting other Reddit posts from HanAssholeSolo, some of which were racist and anti-Semitic. Here's another meme from the guy Trump tweeted, this one showing CNN personalities with Jewish stars.

Trolls then started attacking Sexton and sending him death threats, he told HuffPost. “There’s a fever pitch to this dialogue that is dangerous to everybody,” Sexton said. “And it’s the people who are mentally ill, who are unhinged, who are unwell — they pick up on this stuff. And they are really, really moved to act by it.” The White House hasn't said where it got the video, nor if it's sorry for using work made by someone who trades in anti-Semitism.

In the days since their old posts were exposed, HanAssholeSolo has wiped all his old Reddit activity — but on Tuesday he posted this apology. Reddit

The post is titled, "To my fellow redditors in this community, the rest of reddit and the media/public, I apologize." The Reddit user apologizes for the controversy, and says he was "trolling" and never supported the hateful things he posted. "As time went on it became an addiction as to how far it could go with the posts that were made," the user wrote. "This has been an extreme wake up call to always consider how others may think or feel about what is being said before clicking the submit button anywhere online that an opinion is allowed." The Reddit user said the CNN video was supposed to be satire and was not intended to promote violence against the press. The apology concluded with an anti-trolling message, encouraging those who engage in such behavior to seek help. "Trolling is nothing more than bullying a wide audience," the user wrote.

The post was quickly locked by the moderators of The Donald subreddit, as was a subsequent repost, which prevented people from viewing or commenting on the apology — but some had already done so. Reddit

When news of the apology reached Twitter, some praised the Reddit user for denouncing trolling. Twitter: @JoshLevs

But many others were skeptical whether the apology was actually sincere. Twitter: @Green_Footballs

Some theorized that the Reddit user was trying to neutralize the controversy and avoid being publicly identified. Twitter: @moogie2015

Sure enough, CNN revealed it had identified and contacted the Reddit user before he posted his apology. CNN discovered HanAssholeSolo's identity through bits of biographical data left on his Reddit.… https://t.co/yqMOkhMZzz

CNN said it was able to identify the man based on "details he had made available on Reddit" that it then corroborated using his other social media platforms. CNN said the Reddit user returned its calls after he posted his apology, and that he thought the White House "should have used their better judgment" before posting the tweet. The network declined to name the man, calling him "a private citizen who has issued an extensive statement of apology" and noting he had promised not "to repeat this ugly behavior on social media again." But it did say also, "CNN reserves the right to publish his identity should any of that change."

This line raised a few eyebrows in media circles. Unusual justification by @CNN for withholding identity of subject. Ever seen anything voiced like this before?… https://t.co/NNRoGJjydE

Not sure how “publicly threatening to dox someone if he does it again” squares with journalistic ethics

WikiLeaks then tweeted that "CNN is worse" than Trump. Trump was bad. CNN is worse: CNN threatens amateur satirist behind Trump video: make fun of us again and we dox you… https://t.co/K9bdvry4xb

Right-wing figures soon began attacking the network and the hashtag #CNNblackmail began trending. @KFILE

Andrew Kaczynski, the CNN reporter who wrote the story, said the line was being misinterpreted. This line is being misinterpreted. It was intended only to mean we made no agreement w/the man about his identity. https://t.co/9FL6EvTikx

Kaczynski also said the Reddit user told him he did not feel threatened by the wording in the story. FYI "HanAssholeSolo" just called me."I am in total agreement with your statement. I was not threatened in anyway." https://t.co/7se1B8Z29D Disclaimer: Kaczynski is a former BuzzFeed News employee.