False claims about COVID-19 vaccines are spreading widely on social media, researchers warn. They could undermine public health efforts to curb the pandemic.
The state and federal officials say Facebook's acquisitions of WhatsApp and Instagram violated competition laws and served to stifle rivals by giving the social network an unfair advantage.
The new ban is an expansion of the social network's rules against misinformation that could lead to imminent physical harm. It comes as governments prepare to roll out the first vaccinations.
The Senate Judiciary Committee grilled Facebook's Mark Zuckerberg and Twitter's Jack Dorsey over how they handle false and misleading claims about the election, including from President Donald Trump.
Backed by Rebekah Mercer, Parler now one of the most downloaded smartphone apps, as conservatives complaining of censorship by Facebook and Twitter seek out other social media alternatives.
Facebook, Twitter, YouTube and TikTok have stepped up efforts to curb the spread of misinformation about the election, but researchers say falsehoods thrive nearly unchecked on live videos.
The group had amassed more than 360,000 members who shared false claims about voter fraud before the social network shut it down, citing "worrying calls for violence" from some members.
Facebook's Mark Zuckerberg, Twitter's Jack Dorsey and Google's Sundar Pichai go before the Senate Commerce Committee to defend Section 230, a law that protects them from lawsuits over users' posts.
The chief executives of Facebook, Twitter and Google face skepticism from a Senate committee over their decisions about what content to allow and what to take down from their platforms.