Among those suspended was Richard Spencer, who runs an alt-right think tank and had a verified account on Twitter.
The alt-right, a loosely organized group that espouses white nationalism, emerged as a counterpoint to mainstream conservatism and has flourished online. Spencer has said he wants blacks, Asians, Hispanics and Jews removed from the U.S.
Twitter on Tuesday removed Spencer's verified account, @RichardBSpencer, that of his think tank, the National Policy Institute @npiamerica, and his online magazine @radixjournal.
"This is corporate Stalinism," Spencer told The Daily Caller News Foundation. In a YouTube video, entitled Knight of the Long Knives, an apparent reference to the purge of Nazi leaders in 1934 to consolidate Adolf Hitler's power, Spencer said Twitter had engaged in a coordinated effort to wipe out alt-right Twitter.
"I am alive physically but digitally speaking there has been execution squads across the alt right," he said. "There is a great purge going on and they are purging people based on their views."
In a statement, Twitter said: "The Twitter Rules prohibit targeted abuse and harassment, and we will suspend accounts that violate this policy."
It declined to comment specifically on the suspensions, which included the accounts of Paul Town, Pax Dickinson, Ricky Vaughn and John Rivers.
Twitter was the platform of choice for the campaign of President-elect Donald Trump and the alt-right political movement that embraced him. The alt-right used social media to spread its cause of white supremacy, operating largely unchecked by social media giants Twitter and Facebook.
Heidi Beirich, spokeswoman for the Southern Poverty Law Center, told USA TODAY that the center had asked Twitter to remove more than 100 accounts of white supremacists who violated Twitter's terms of service. She also pointed to two alt-right accounts that had been verified by Twitter, including Spencer's.
Twitter says it verifies an account by giving it a blue check mark when "it is determined to be an account of public interest." Twitter launched the feature in 2009 after celebrities complained about people impersonating them on the social media service.
"We are encouraged by the decisions taken by Twitter. Now it is a matter of whether they are carried out," Beirich said. "Obviously, well-known white supremacists violate these terms of service and we are glad it appears that Twitter has chosen to step up on these issues."
Twitter has suspended alt-right accounts in the past but never so many at once.
In one of the highest-profile bans, Twitter removed the account of Milo Yiannopoulos, a technology editor at the conservative news site Breitbart in July. He had engaged in a campaign of abuse in which hundreds of anonymous Twitter accounts bombarded Ghostbusters actress Leslie Jones with racist and sexist taunts. Before banning Yiannopoulos, Twitter stripped him of his verified status.
Spencer said he supported Yiannopoulos and didn't think he should have been banned from Twitter. But, he said in his YouTube video, "Milo was engaging in something that could be called harassment."
"The fact is that I, and a number of other people who have just got banned, weren't even trolling," he said. "I was using Twitter just like I always use Twitter, to give people some updates and maybe to comment on a news story here and there."