Facebook chief executive Mark Zuckerberg took to his social network Wednesday to condemn white supremacists and pledged to remove violent threats and posts celebrating hate crimes.

“The last few days have been hard to process,” Zuckerberg wrote on his Facebook page Wednesday evening, days after a white supremacist rally in Charlottesville, turned deadly. “As a Jew, it’s something I’ve wondered much of my life. It’s a disgrace that we still need to say that neo-Nazis and white supremacists are wrong — as if this is somehow not obvious. My thoughts are with the victims of hate around the world, and everyone who has the courage to stand up to it every day.”

Zuckerberg’s comments come amid a wave of action by technology companies to more assertively police controversial speech. This week, for example, both GoDaddy and Google blacklisted the neo-Nazi site the Daily Stormer. And Facebook said it had begun “actively removing any posts” celebrating the killing on Saturday of Heather Heyer, who died when a suspected white supremacists ran his car over counterprotesters. The social network also removed several pages devoted to white nationalism, according to BuzzFeed. PayPal said Tuesday it would shut off its services to groups like the KKK, cutting off what the Southern Poverty Law Center has called “the banking system for white nationalism.”

As the world’s largest social network, with more than 2 billion users, Facebook aims to support a global platform for free expression while sustaining a forum where its community of users feel welcomed. From a free-speech perspective, opinions that people agree with and detest should be freely accessible, said Roy Gutterman, director at the Tully Center for Free Speech at Syracuse University. “But the other problem is: How much do you legitimize fringe organizations by letting them have a real place at the table?”

In recent years, Facebook and other social media companies have come under increasing criticism for not doing enough to combat propaganda and extremist rhetoric. After the terrorist attack in London earlier this year, British Prime Minister Theresa May attacked Web companies for providing a “safe space” for people with violent ideologies.

The scope of brutality in Charlottesville seemed to reignite similar concerns. “It is their responsibility to figure out a way not to be complicit with these types of violent actions — or become comfortable with the fact that they are,” Charlton McIlwain, a professor at New York University who focuses on race and digital media, told Wired.

Looking ahead, with the potential for more white supremacist rallies, Zuckerberg said, “We’re watching the situation closely and will take down threats of physical harm. We won’t always be perfect, but you have my commitment that we’ll keep working to make Facebook a place where everyone can feel safe.”