In an unusually public response to harassment charges, Twitter permanently banned controversial columnist Milo Yiannopoulos from its platform Tuesday night. Yiannopoulos, who works for the conservative website Breitbart.com, had been charged with inciting a storm of racist tweets against “Ghostbusters” star Leslie Jones, which prompted the actress to announce her own departure from Twitter earlier this week.

“No one deserves to be subjected to targeted abuse online, and our rules prohibit inciting or engaging in the targeted abuse or harassment of others,” a Twitter spokesperson said via email. The statement didn’t mention Yiannopoulos by name, but said that Twitter had taken actions against a number of accounts, “ranging from warnings that also require the deletion of Tweets violating our policies to permanent suspension.” The ban of Yiannopoulos was first reported by Buzzfeed.

Yiannopoulos had long been credited with inciting mob-like behavior among his followers, and frequently picked on liberals, women and people of color. He became a champion of the so-called GamerGate movement, and was temporarily banned from Twitter before. At one point, he had tweeted that one of his victims “deserves to be harassed.”

Yiannopoulos responded to the now-permanent ban by calling it “cowardly” and predicting that this would harm Twitter. “Anyone who cares about free speech has been sent a clear message: you’re not welcome on Twitter,” he was quoted on Breitbart.com.

Victims of online harassment have long argued that Twitter hasn’t done enough to curb hateful speech and abuse. Tuesday’s response may indicate that the company is changing its tone on the issue. It was particularly notable because CEO Jack Dorsey himself intervened, at one point asking Jones with a tweet to contact him privately to discuss her concerns.