Twitter has made good — so far — on its pledge to crack down on tweets that contain false or misleading information about COVID-19 cures. The platform has deleted tweets by the presidents of Brazil and Venezuela and former New York City Mayor Rudy Giuliani for violating its ban on novel coronavirus-related content that “goes directly against guidance from authoritative sources of global and local public health information.”

“We’re focused on protecting the public conversation and helping people find authoritative sources of information on Twitter. There have been a number of measures we’ve taken in regard to COVID-19,” a Twitter spokesperson said in an email to The Verge. “We’ll continue to review and require the removal of Tweets that do not follow the Twitter Rules. This is an evolving global conversation and we’re committed to remaining vigilant.”

President Jair Bolsonaro of Brazil had two tweets removed on Sunday which included videos of him endorsing hydroxychloroquine and calling for an end to social-distancing efforts, BuzzFeed News reported. Both chloroquine and hydroxychloroquine are still unproven as potential treatment options for COVID-19.

Bolsonaro said in one of the videos that he has been hearing from Brazilians that they want to return to work. “Brazil cannot stop or we’ll turn into Venezuela.”

Facebook also removed a video of Bolsonaro from its main social network and Instagram on Monday, according to BBC News Brasil. “We remove content on Facebook and Instagram that violates our Community Standards, which do not allow misinformation that could lead to physical harm,” said Facebook in a statement about the removal to The Verge. Facebook removed the video because of Bolsonaro’s endorsement of hydroxychloroquine, reports BuzzFeed News’ Ryan Mac. The company confirmed that reasoning to The Verge.

Twitter had earlier removed a tweet by Venezuela’s President Nicolás Maduro (which is probably not what Bolsonaro was referring to) that endorsed a “brew” that would “eliminate the infectious genes” of the novel coronavirus. Twitter has had a long-standing position against removing tweets by world leaders unless the tweets violated Twitter’s rules with no room for interpretation, as BuzzFeed News notes.

And on Friday, Twitter removed a tweet from Giuliani which quoted a tweet by conservative writer Charlie Kirk suggesting that hydroxychloroquine had a “100% effective rate treating COVID-19,” Mediaite reported. Kirk’s tweets were also deleted.

Twitter outlined its COVID-19 policies in a blog post on March 4th, stating that it was taking a “zero-tolerance approach to platform manipulation and any other attempts to abuse our service at this critical juncture.”

It’s since removed misleading COVID-19 tweets by the likes of actress Alyssa Milano and businessman John McAfee. It also locked The Federalist’s Twitter handle after it promoted tweets endorsing so-called coronavirus chicken pox parties where people would deliberately expose themselves to infection. This is not recommended by medical authorities.

Update March 30th, 8:01PM ET: Added confirmation that Facebook removed Bolsonaro’s video because of his endorsement of hydroxychloroquine.