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.