The far-right web forum 8chan, used to celebrate mass shootings and spread suspects' so-called “manifestos”, has been forced offline after losing its cyber-security protection.
Cloudflare, a San Francisco-based firm that provides added security for websites to prevent cyber-attacks, said it would stop protecting 8chan at midnight Pacific Time (08:00 BST) on Monday.
The 21-year-old suspect in this weekend’s shooting in El Paso, Texas, is understood to have used 8chan to spread his manifesto.
Previously, the site was also used by the suspect in March’s shooting in Christchurch, New Zealand, as well as the suspect in April's synagogue shooting in Poway, California.
Losing Cloudflare’s protection has made 8chan vulnerable to a Distributed Denial of Service (DDoS) attack, whereby a website is bombarded with traffic that overwhelms its servers, rendering it inaccessible.
A few minutes after the Cloudflare service was withdrawn, 8chan did indeed become unavailable.
However, 8chan's site administrator says it was moving to another security firm, BitMitigate, based in the US state of Washington. BitMitigate's website says it has "a proven commitment to liberty".
BitMitigate stepped in to help neo-Nazi site the Daily Stormer when it lost Cloudflare protection in 2017.
The BBC has approached BitMitigate for comment. But at this time 8Chan remains offline.
Cloudflare chief executive Matthew Prince had said, in the wake of Saturday’s shootings, that his firm would continue to support 8chan as its policy was to remain neutral over the type of content the service protected.
However, on Sunday evening Mr Prince wrote in a blog post that "8chan has repeatedly proven itself to be a cesspool of hate”.
“They have proven themselves to be lawless and that lawlessness has caused multiple tragic deaths,” Mr Prince wrote.
"Even if 8chan may not have violated the letter of the law in refusing to moderate their hate-filled community, they have created an environment that revels in violating its spirit.”
Mr Prince warned that while 8chan would be disrupted by Cloudflare’s decision, it would likely be able to rebuild itself - as was the case when Cloudflare stopped providing protection for the Daily Stormer, a neo-Nazi site, in 2017.
“They quickly came back online using a Cloudflare competitor,” Mr Prince wrote.
"That competitor at the time promoted as a feature the fact that they didn't respond to legal process.
He added: "I have little doubt we'll see the same happen with 8chan. While removing 8chan from our network takes heat off of us, it does nothing to address why hateful sites fester online. It does nothing to address why mass shootings occur. It does nothing to address why portions of the population feel so disenchanted they turn to hate.
"In taking this action we've solved our own problem, but we haven't solved the internet’s.”
How do Cloudflare and BitMitigate services work?
The two companies protect websites from attacks, as well as making websites load more quickly for legitimate users.
They can be thought of as a kind of bouncer or security guard for websites that get a large amount of traffic, or may be a likely target of cyber-attacks.
They use technology that can verify where internet traffic is coming from and what it is trying to do.
They can distinguish whether the visitor is a genuine person, a network of automated bots that is being used to flood a website or requests that keep servers too busy to handle normal uses.
They are meant to block any attempts from "bad" traffic getting through.
Cloudflare provides protection for more than 12 million websites, and is expected to float on the stock market later this year.
Chief executive Matthew Prince has expressed concern at the power his company has to decide whether or not a website is able to exist on the open internet.
8chan is a forum created in 2013 by Fredrick Brennan as an alternative to 4chan, a message board popular with gamers. 8chan promised less moderation of controversial topics and images that were being removed from 4chan. As such, 8chan has hosted far-right extremist views and imagery.
Mr Brennan gave up ownership of 8chan in 2015 and has since called for it to be shut down. Following Cloudflare’s announcement, he wrote on Twitter: "Thank you so much @CloudFlare Finally this nightmare might have an end.”
8chan is now owned and run by Jim Watkins, a former US army veteran, believed to be living in the Philippines.
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