New rules implemented on Twitter Monday have led to the suspensions of accounts belonging to prominent neo-Nazis, white nationalists and other far-right extremists.

Jayda Fransen, a leader of Britain First, a virulently anti-Muslim extremist group in the United Kingdom, got booted off the social media network Monday. Fransen gained notoriety in the United States late last month when President Donald Trump retweeted her three times.

Screenshot of Twitter

Other accounts kicked off Twitter include those belonging to Jared Taylor, editor of the white supremacist magazine American Renaissance (which also had its verified account closed); Brad Griffin, aka Hunter Wallace, of League of The South, who helped organize a recent White Lives Matter rally in Tennessee; Jeff Schoep, head of the National Socialist Movement, a neo-Nazi group; Vanguard America, the white nationalist group to which James Alex Fields Jr., who drove his car through protesters in Charlottesville, belonged; Michael Hill, another leader in League of the South; the Traditionalist Worker Party, a white nationalist group whose co-founder was the recent subject of a sympathetic New York Times profile; Generation Identify, a European white “identitarian” group; the American Nazi Party; the English Defense League, an anti-Muslim group; and the Canadian chapter of the Jewish Defense League, a violent far-right and pro-Israel group.

Twitter announced in mid-November that beginning Dec. 18, it would consider account user behavior “on and off the platform” when deciding whether to close down an account, as part of an effort to “reduce hateful and abusive content.”

“You may not make specific threats of violence or wish for the serious physical harm, death, or disease of an individual or group of people,” states Twitter’s rule for “violent extremist groups,” which went into effect Monday.

“This includes, but is not limited to, threatening or promoting terrorism,” the rule continues. “You also may not affiliate with organizations that – whether by their own statements or activity both on and off the platform – use or promote violence against civilians to further their causes.”

The new rules were a response to years of outrage over Twitter allowing hate to flourish on its site. There was a particularly strong backlash last month when Jason Kessler, the white nationalist organizer of the violent “Unite The Right” rally in Charlottesville, Virginia ― which resulted in the death of counter-protester Heather Heyer — was verified by Twitter, receiving the blue checkmark that lends accounts an air of legitimacy. Twitter eventually revoked his verification, as it did to some other prominent white nationalists, including Richard Spencer.

The “alt-right ― a loose association of neo-Nazis, white nationalists, assorted racists, fascists, and other far-right elements that has used Twitter for years to organize and recruit ― anticipated today’s “purge,” with many preparing to make the jump to Gab, a largely rules-free micro-blogging platform used primarily by white nationalists.

Press F pic.twitter.com/WjvizzGO69 — Gab: Free Speech Social Network (@getongab) December 18, 2017

Gab’s official Twitter account has gleefully documented Monday’s developments, tweeting “Press F” whenever another user account was shuttered, a reference to the video game “Call of Duty,” in which players are asked to “press F to pay respects” during a funeral for a character killed in the game.

Gab also used Monday’s”purge” to hold itself up as a paragon of free speech. In one Tweet, it compared Twitter to Soviet dictator Joseph Stalin.

Susan Benesch — a member of Twitter’s Trust & Safety Council who serves as executive director of the Dangerous Speech Project and is a faculty associate at Harvard University’s Berkman Klein Center for Internet & Society — told Mashable on Monday that Twitter’s new rules could be a “slippery slope.”

“If Twitter starts banning people who are affiliated with organizations that use or promote violence against civilians to further a cause, that’s tantamount to prohibiting certain opinions: a very new policy for a platform that used to be known as the ‘free speech wing of the free speech party,’” Benesch said.

“It’s not surprising, of course,” she continued. “If you’re going to ban any kind of opinion, this is a logical place to start. Twitter staff may find themselves struggling to distinguish among guerrillas, terrorists, revolutionaries, and dissidents.”

Still, as of Monday afternoon, the purge wasn’t as widespread as many had expected. Many prominent white nationalist Twitter accounts remained active, including those belonging to Richard Spencer, Mike Peinovich (aka Mike Enoch), Elliot Kline (aka Eli Mosley), Evan McLaren, James Allsup, Nathan Damigo, Nicholas Fuentes, David Duke and Jason Kessler.

As of now, I don't see any systematic method to the #TwitterPurge. I've lost more than a hundred followers in 24 hrs, but lots of pro-White accounts, even shit-lordy ones, remain. @jartaylor got purged, but not @Steve_Sailer, @vdare, @TOOEdit , et al. Haphazard. — Richard 🎄 Spencer (@RichardBSpencer) December 18, 2017

In a statement Monday, the Anti-Defamation League commended Twitter for “taking these significant steps to tackle hate on their platform. We have long urged Twitter to push back against hateful and violent rhetoric and these latest actions are encouraging.”

The civil rights group Muslim Advocates also applauded Twitter’s new rules.

“As social media sites have become the central organizing hub for America’s hate groups, companies like Twitter and Facebook have a responsibility to ensure that their platforms are not used to sow violence and hate,” the group said in a statement.

Asked Monday if Twitter’s new rules would stop Nazis and their ilk from just opening new accounts after being kicked off the site, a Twitter spokesperson told HuffPost that the company takes “preventative measures to help keep accounts that have been suspended from popping up under new guises, though we don’t discuss those measures publicly lest we inadvertently make it easier for suspended users to evade such measures.”

In its official statement on the new rules Monday, Twitter also acknowledged that enforcing the new rules is going to be a messy business.

“In our efforts to be more aggressive here, we may make some mistakes and are working on a robust appeals process,” it said. “We’ll evaluate and iterate on these changes in the coming days and weeks, and will keep you posted on progress along the way.”