Gab, the social media site popular with the far-right, has been forced offline by its service providers after it became clear that the alleged Pittsburgh shooter Robert Bowers had a history of antisemitic postings on the site.

Formed in August 2016 after Twitter began cracking down on hate speech on its social network, Gab has been labelled “Twitter for racists” by the website Salon but describes itself as “a free speech website and nothing more”. But the platform has proved popular among white supremacists, neo-Nazis and the “alt-right”, including the man accused of opening fire on a synagogue in Pennsylvania on Saturday, killing 11.

“I can’t sit by and watch my people get slaughtered,” the alleged assailant wrote, moments before the murders. “Screw your optics, I’m going in.” It was his last post on the site.

In the hours following the attack, when the suspect’s postings were discovered on the site, Gab’s corporate partners abandoned it one by one. PayPal and Stripe, two of the company’s payment providers, dropped it, arguing that it breached policies around hate speech. PayPal said it takes “immediate and decisive action … when a site is explicitly allowing the perpetuation of hate, violence or discriminatory intolerance,” while Stripe said that the company had not provided sufficient evidence that it actually applies its moderation policies in practice.

Cloud-hosting company Joyent also withdrew service on Sunday, giving Gab 24 hours notice of its suspension, as did GoDaddy, the site’s domain registrar, which provides the Gab.com address. Both companies said the site had breached their terms of service.

GoDaddy added that it had “investigated and discovered numerous instances of content on the site that both promotes and encourages violence against people”.

Gab hit back, saying in a statement that the site is “under attack.”

“We have been systematically no-platformed by App Stores, multiple hosting providers, and several payment processors,” the company said in a statement posted to its site. “We have been smeared by the mainstream media for defending free expression and individual liberty for all people and for working with law enforcement to ensure that justice is served for the horrible atrocity committed in Pittsburgh.”

Gab is not the only social network accused of failing to apply its own policies against hate. On Saturday, Twitter apologised for its failure to take action against the chief suspect of a wave of attempted mail bombings, Cesar Altieri. He had been reported to the social network for threatening others, including journalist Rochelle Ritchie.

Breaking: @joyent, Gab’s new hosting provider, has just pulled our hosting service. They have given us until 9am on Monday to find a solution. Gab will likely be down for weeks because of this. Working on solutions. We will never give up on defending free speech for all people. pic.twitter.com/YvnBOFoQQn — Gab.com🍂 (@getongab) October 28, 2018

“Hug your loved ones real close every time you leave you home,” Altieri tweeted at Richie earlier this month, in one of many tweets reported for violating policies against threatening language. But Twitter took no action against Altieri’s tweets, a fact the company apologised for over the weekend.

“We made a mistake when Rochelle Ritchie first alerted us to the threat made against her,” the company said. “The tweet clearly violated our rules and should have been removed. We are deeply sorry for that error.”

BREAKING: @stripe is likely going to ban us. We gave them plenty of documented and detailed evidence. The no-platforming continues. pic.twitter.com/HQq5YSCaJN — Gab.com🍂 (@getongab) October 28, 2018

A profile on the site maintained by the alleged shooter, 46-year-old Robert Bowers, surfaced the immediate aftermath of the Pittsburgh shooting, which left eleven people dead and several others wounded. Screenshots revealed that Bowers had published numerous anti-Semitic conspiracy theories, and that has placed Gab under increased scrutiny. While Gab says that it immediately suspended the man’s account and has cooperated with authorities, it has bristled at the suggestion that it was responsible for the environment that has made it an attractive home to those in the alt-right.

Gab has already been booted from other major platforms: Apple and Google have either prevented the site from releasing its app on their mobile stores, while earlier this summer, Microsoft threatened to drop its hosting if the site didn’t remove a pair of anti-Semitic posts within 48 hours. A Microsoft spokesperson told The Verge that the company “terminated its Azure agreement with Gab last month.” Last night, Gab said that it expected to be banned by Facebook and Twitter “soon.”

We’ve reached out to Stripe, and Joyent for comment, and will update this post if we hear back.