The videos—all linked to Iran’s anti-government protests—have all been posted to Twitter. They’ve been shared thousands of times and viewed by hundreds of thousands of people. However, they are just a small snapshot of the Twitter posts coming out of Iran, as the social media platform has played an important role in documenting the brutality faced by protesters. Every day for the past two months, countless Iranians have taken to the streets in more than 150 cities to protest the death of 22-year-old Mahsa Amini, who died in the custody of Iran’s “morality police” after they arrested her for not wearing a hijab in public. Protesters have called for greater women’s rights and regime change in Iran. As they have done so, they have been met with increasing violence from Iranian forces. According to the Human Rights Activists’ News Agency (HRANA), more than 450 protestors have been killed, including 64 children. More than 18,000 people have been arrested, the organization says. Twitter—and social media in general—has been awash in videos appearing to show protesters being attacked by police forces, the bodies of those killed, and people’s injuries. For more than a decade, the social network, now owned by Elon Musk, has been used as a way to document protests and human rights abuses around the world. However, as Musk’s chaotic takeover unravels and key safety teams have been cut, the Iranian protests put fresh light on Twitter’s importance as a platform for information sharing and chronicling events globally. Twitter has made it possible for the world to see attacks on protesters and revealed the horror of those killed. And in a country where the media is tightly controlled by the government, it provides a lifeline for Iranians to access impartial information. “There is the power of Twitter in terms of how effective it is when Iranians themselves are getting online to express their messages directly to the world,” says Mahsa Alimardani, an academic at the Oxford Internet Institute and senior researcher at digital rights group Article 19 who has studied Iran’s internet controls. “Every day I see a new family member of a political prisoner coming online on Twitter to directly start advocating for their kids.” Internet experts and others monitoring the protests are concerned that Musk’s takeover of Twitter will damage a key platform for protest and activism at a time when internet freedoms are being curtailed. For the past decade, Iran has created tools to shut down the internet and block social media platforms. While it has blocked Twitter on and off since 2009, the country’s censorship tools have become increasingly sophisticated. In 2019, it shut down the entire internet as people rallied against rising fuel prices. During the protests following Amini’s death, Iran has targeted its internet controls: Digital curfews have been in place, and WhatsApp, Instagram, Skype, Viber, and LinkedIn have all been blocked. “Iran is one of the world’s worst abusers of internet freedom. It ranks down there with China and Russia,” says Cathryn Grothe, a research analyst for the Middle East and North Africa at Freedom House, a nonprofit that produces an annual report on internet freedom. As a result of the curfews and blocks, there has been a surge in Iranians using virtual private networks and censorship circumvention tools to get online. Videos and images shared by protesters have been used to shine a light on the actions of the Iranian police forces and officials. A BBC investigation has used social media data to help identify young people and children killed in the nationwide protests. There is no official record of those who have died during the protests, and HRANA estimates that only 3,400 people who have been detained by officials have been identified. More than 18,000 have been arrested. High-profile accounts both inside and outside Iran, belonging to those on the ground, members of the Iranian diaspora, and researchers, are sharing hundreds of videos of what is happening in Iran. For example, opposition activist collective 1500tasvir has seen its Farsi Twitter account grow from 55,000 followers in September to around 400,000 followers now. (In the past two months its Instagram account has also jumped from 450,000 followers to 1.7 million.) “You cannot find any normal or correct news from Iranian TV, because there is no independent platform inside the country,” says Saeed Bagheri, a lecturer in international law at the University of Reading. Bagheri says those using Twitter in Iran have been “really effective in sharing firsthand news about human rights violations and Islamic republics of brutality against peaceful protests.” On November 24, the United Nations opened an investigation into “deadly violence against protesters,” citing images of those who had been subjected to violence. Iranian officials claimed “necessary measures” had been taken by authorities. However, it is not only Iranian protesters and activists using Twitter. Iranian state-backed actors have a history of trying to use Twitter to manipulate politics. In June 2019, Twitter removed almost 5,000 accounts associated with or “directly backed” by the Iranian government. These accounts—which tweeted around 2 million times—were pushing the views of the Iranian government and used fake profiles to “target conversations about political and social issues in Iran and globally.” One Iranian digital propaganda researcher, who asked not to be named for security reasons, says they have been monitoring the most popular Farsi tweets for several months. Before the protests started, they say, accounts that appear to support the Iranian government pushed messages that were justifying its policies. Once the protests started, accounts pivoted to sharing mis- and disinformation about the events, they say. “I have never seen such a big and massive effort in pouring the Iranian Twitterverse with false information. But the regime was not successful in this regard.” Twitter has long been a place where protests have been organized. However, Musk’s takeover of the platform and the chaotic scenes that have followed—including gutting Twitter’s human rights team—could have real-world consequences where protests are taking place. This could include the ability to keep people safe. The Oxford Internet Institute and Article 19’s Alimardani says that much of Musk’s time in charge has so far focused on US issues despite the fact that the majority of Twitter users are from outside of the United States. “Iranians don’t care that Elon Musk is waging a war against woke culture in America,” Alimardani says. “Iranians just want to get their message to the world as fast and efficiently as possible.” “Article 19 is highlighting clear instances of human rights abuses being platformed on Twitter,” Alimardani says. “These conversations are much more difficult and cumbersome to have right now,” Alimardani adds. As highlighted by BBC journalist Shayan Sardarizadeh, it took multiple days for Twitter to suspend an account that appeared to be linked to Iran’s Revolutionary Guard. The account, which had 91,000 followers, was allegedly posting images of protesters who had been attacked. It is likely the tip of the iceberg. “There are still hundreds of accounts of users that are tied to the state or clearly tied to the security forces that are still posting forced confessions,” Alimardani claims. (Twitter, which is believed to no longer have a communications department, did not reply to WIRED’s request for comment.) Rashidi adds that Musk’s announcement that suspended Twitter accounts would be given an “amnesty” is a particular cause for concern. He highlights pro-Iranian government accounts that have been removed in the past for violating Twitter’s rules. “They were going after activists. They were harassing individuals. They were even putting out videos of forced confessions on their accounts,” Rashidi says. If those accounts return, Rashidi adds, Twitter will be less safe for Iranians.