A San Francisco-based Web company announced Sunday it would no longer provide services to 8chan, a website notorious for hosting lawless message boards where manifestos have appeared before mass shootings.

The move came after a screed against immigrants was posted to 8chan shortly before a mass shooter killed 20 and wounded 26 at an El Paso Walmart and shopping center. Matthew Prince, CEO of Cloudflare, a firm that protects sites from cyber attacks, said he decided to drop 8chan because it “has repeatedly proven itself to be a cesspool of hate.”

“We reluctantly tolerate content that we find reprehensible, but we draw the line at platforms that have demonstrated they directly inspire tragic events and are lawless by design,” Prince said in a blog post about his decision. “8chan has crossed that line. It will therefore no longer be allowed to use our services.”

Calls to de-platform the site had intensified Sunday as authorities worked to confirm that Patrick Crusius, the 21-year-old suspect in the El Paso shooting, had posted a manifesto decrying a “Hispanic invasion of Texas” to 8chan before the attack. The suspected shooters at mosques in Christchurch, New Zealand, and a synagogue in San Diego also reportedly posted on the site before carrying out their attacks. On Sunday, some 8chan message boards celebrated the El Paso massacre.

The site’s founder, Fredrick Brennan, was among those calling for 8chan to be shut down after the El Paso shooting. Brennan founded 8chan in 2013 but ceased working with its owners in December.

The anonymous message board houses some of the most controversial content online. Here’s a look behind its rise in influence. (Adriana Usero, Melissa Macaya, Deirdra O'Regan/The Washington Post)

“Once again, a terrorist used 8chan to spread his message as he knew people would save it and spread it,” Brennan told The Washington Post’s Drew Harwell. “The board is a receptive audience for domestic terrorists.”

When Prince announced that his firm would no longer work with 8chan, Brennan celebrated the news on Twitter, writing, “Finally this nightmare might have an end.”

It seems unlikely, though, that Prince’s decision will keep 8chan off the Web for long. He acknowledged as much, noting that he decided to stop working with the Daily Stormer, the Web’s most prominent neo-Nazi website, two years ago. The site quickly found another firm to protect its network and returned to the Web.

“Today, the Daily Stormer is still available and still disgusting. They have bragged that they have more readers than ever. They are no longer Cloudflare’s problem, but they remain the Internet’s problem,” Prince wrote. “I have little doubt we’ll see the same happen with 8chan.”

Indeed, Ron Watkins, who helps oversee 8chan, tweeted on Sunday night that he was working to restore the site by switching to a new service.

Jim Watkins, an American entrepreneur living in the Philippines whose Nevada-based company is listed as 8chan’s owner, replied to The Post’s request for comment on Sunday with one line: “I hope you are well.”

Prince wrote that his decision to stop working with 8chan was not easy, despite the mounting public pressure to do so. He said his firm is “incredibly uncomfortable about playing the role of content arbiter,” and urged politicians to work toward a more standard framework for dealing with “lawless” sites.

“While we’ve been successful as a company, that does not give us the political legitimacy to make determinations on what content is good and bad. Nor should it,” Prince wrote. “Questions around content are real societal issues that need politically legitimate solutions.”

Without those solutions, he argued, sites like 8chan and the Daily Stormer will inevitably find ways to continue operating.

“While removing 8chan from our network takes heat off of us, it does nothing to address why hateful sites fester online,” Prince wrote. “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.”

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