One month after it distinguished itself from the rest of the tech industry by declining to bar the rightwing conspiracy theorist Alex Jones from its platform, Twitter fell in line Thursday, permanently banning the accounts of both Jones and his website Infowars.

“We took this action based on new reports of Tweets and videos posted yesterday that violate our abusive behavior policy, in addition to the accounts’ past violations,” the company tweeted. “We will continue to evaluate reports we receive regarding other accounts potentially associated with @realalexjones or @infowars and will take action if content that violates our rules is reported or if other accounts are utilized in an attempt to circumvent their ban.”

The company does not usually comment on individual accounts, but said it “wanted to be open about this action given the broad interest in this case”. The two accounts had about 1.3 million followers combined.

The decision comes just 24 hours after both Jones and Twitter’s chief executive, Jack Dorsey, spent the day on Capitol Hill, where Dorsey testified before committees of the House and Senate and Jones roamed the hallways, accosting politicians and reporters.

The 44-year-old Jones is perhaps best known for spreading a conspiracy theory that has resulted in years of harassment for the parents of victims of the Sandy Hook elementary school shooting. His broadcasts and website feature a mix of false information, hate-mongering, conspiracy theories and general ranting.

Facebook, YouTube, Twitter, Spotify and Apple Podcasts all allowed Jones to use their platforms to build his following until this summer, when a reporter from CNN, Oliver Darcy, publicly asked Facebook to explain how it could claim to combat hate speech and misinformation while continuing to amplify Jones.

Facebook prevaricated until early August, when a decision by Apple to remove Infowars from its podcasting app precipitated a storm of bans from social media platforms. Twitter was the sole high-profile holdout.

“We’re going to hold Jones to the same standard we hold to every account, not taking one-off actions to make us feel good in the short term, and adding fuel to new conspiracy theories,” Dorsey tweeted at the time.

On 15 August, Jones’s account was temporarily suspended for abusive tweets.

Twitter did not explain exactly how Jones had violated its rules this time, but during his trip to the Capitol, Jones got into an altercation with the Florida senator Marco Rubio and used Twitter’s video app Periscope to broadcast himself yelling at Darcy for about 10 minutes.

An analysis by the New York Times this week found that Jones’ audience has decreased significantly in the wake of his bans from Facebook and YouTube. The figures suggest that together the two social media platforms were responsible for doubling Jones’ audience.