Twitter has suspended several accounts linked to the alt-right movement, which has been associated with white nationalism.
The move comes as Twitter is rolling out a series of actions to curb hate speech and abuse on its platform as criticism has mounted of the company's failure to rein in harassment, racism, sexism and anti-Semitism.
Suspended accounts include those of Richard Spencer, who is considered one of the movement's founders; his magazine Radix Journal; an associated account, @_AltRight_; and his Virginia-based think tank called the National Policy Institute, whose website describes it as "dedicated to the heritage, identity, and future of people of European descent in the United States, and around the world."
Other suspended accounts include those of prominent alt-right members Pax Dickinson, former chief technology officer of Business Insider, and Ricky Vaughn, who has been suspended in the past.
In a YouTube video titled The Knight of Long Knives, Spencer says he and others weren't trolling or harassing anyone on Twitter but were posting to "give people some updates and maybe comment on a news story here and there."
"It is corporate Stalinism, in a sense that there is a great purge going on and they're purging people on the basis of their views," Spencer says in the video, later adding: "Social media did help elect Trump. This is a clear sign that we have power. ... We have power and we're changing the world and they're not going to put up with it anymore."
Asked for comment, Twitter pointed NPR to its rules, which "prohibit violent threats, harassment, hateful conduct, and multiple account abuse, and we will take action on accounts violating those policies."
Twitter's policy defines hateful conduct pretty broadly as attacks or threats or promotion of violence against people "on the basis of race, ethnicity, national origin, sexual orientation, gender, gender identity, religious affiliation, age, disability, or disease."
Among examples of behavior that Twitter won't tolerate, the company lists references to mass murder or violence that has primarily targeted or victimized a protected group, actions that incite fear about a protected group, and repeated slurs or degrading language.
This week, Twitter is making the biggest expansion yet of the tools available to users to report or avoid seeing offensive and abusive language. The social platform is allowing people to "mute" not just particular accounts but also words, phrases or conversations.
Earlier this year, Twitter permanently banned conservative Breitbart writer and prominent alt-right member Milo Yiannopoulos amid a campaign targeted at Ghostbusters and Saturday Night Live star Leslie Jones, who temporarily left Twitter under a barrage of abusive messages.