Roger Stone, a longtime adviser to President Donald Trump, has been suspended from Twitter following a rant against two CNN reporters.

It is one of the highest-profile account suspensions since Twitter has said it will take stronger action against bullying and threats of violence on its service.

Stone's account was taken offline on Saturday night following a series of profane attack tweets he put out on Friday focused on CNN reporters Don Lemon and Jake Tapper.

".@donlemon stop lying about about the Clinton's and Uranium you ignorant lying covksucker !!!! You fake news you dumb piece of shit," Stone wrote [sic], according to The Hollywood Reporter, one of the first outlets to report on the ban. He also called Lemon "dumber than dog shit" and wrote that "[e]ven the people at CNN say u are a buffoon behind you back[sic]."

Going after Tapper, Stone wrote: ".@jaketapper must be held accountable for his lies and very severely punished #Fakenewsasswipe." More of the Stone Twitter attacks were saved by TechCrunch.

Stone told Politico that he was told his account suspension would last "three hours and 22 minutes," but it was later reported that Stone would be permanently banned from the service.

Twitter has declined to comment on the matter, citing its policy of not talking about actions over individual accounts.

Stone condemned Twitter following the ban, telling Politico that "the battle against free speech has just begun" and that he will take legal action against Twitter.

"This is a strange way to do business and part and parcel of the systematic effort by the tech left to censor and silence conservative voices," Stone told Politico in a Sunday e-mail.

Earlier this year, Twitter addressed complaints that President Donald Trump had violated the service's rules with threatening tweets. Twitter said that its rules are enforced "the same way for everybody." When it comes to removing tweets, the company added that one of the considerations is whether a tweet is of public interest or not.

The high-profile ban of Stone comes as executives from Twitter, along with Facebook and Google, are set to testify on Capitol Hill about Russian meddling in the 2016 election.

Stone has no government job and doesn't work for the President in any official capacity. But he has been close to Trump since at least 2000, when Trump first toyed with the idea of running for president. Stone helped Trump's campaign throughout 2016. And since the election, Stone has been a stalwart ally of Trump, attacking the president's critics on Twitter and elsewhere.

He has spent his career as a Republican political operative and for years worked for Richard Nixon, whom he admires greatly. Several years ago, Stone got a tattoo of Nixon on his back. In 2017, his work over the years was profiled in a Netflix original documentary called Get Me Roger Stone.

Stone has access to at least two other Twitter accounts through which he has continued to press his case. One is affiliated with his blog Stone Cold Truth, and another is related to the Netflix documentary about him.