Fredrick Brennan, the founder of a message board known as one of the darkest corners on the internet, says the website 8chan has gone too far.
The alleged gunman who killed 50 people when he open fired inside two Christchurch mosques on Friday posted a message on the website saying he would commit the terror attack just hours before he carried it out and livestreamed it on Facebook.
There have since been comments and memes on the site praising the gunman's actions and his white supremacist-views.
Now, Brennan, who is no longer associated with the website, said he believed the administrators of 8chan were too slow in removing the post.
In an interview, Brennan told the Wall Street Journal that he found the days after the shooting difficult knowing that he had created the website.
He said the website and the toxic culture within it would likely result in another mass shooting.
"It wouldn't surprise me if this happens again," he said.
Brennan, 25, spent years moderating the site which is known to be home to racist and abusive content, and harassment campaigns promoting violence. He worked as an administrator up until 2016 and until December worked for the owners of the website.
"I just feel like I wasted too much time on this stuff," Brennan said, expressing regret in the interview with the Journal.
"I didn't spend enough time making friends in real life."
8chan is similar to another site called 4chan but discussions are heavily driven by images. It is understood to attract around 100,000 people to the site daily.
On the 8chan the alleged Christchurch mosque shootings gunman posted an 80-page manifesto and called on members to spread his message.
Following the attack users have reportedly posted hundreds of messages, videos and altered photos of the shooting with the intention of creating viral memes and promote division.
NZ internet service providers including Spark, Vodafone, 2degrees and Vocus have blocked several sites hosting footage of the attack, which has been banned by NZ Chief Censor David Shanks.
The telcos have not published a running list of banned sites, but the user reports indicate it includes both 4chan and 8 chan.
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