Twitter CEO Dick Costolo is tired of trolls.

In a new interview with London’s Financial Times, Costolo announced that the microblog service will take new measures to fight trolling and hate speech on the site.

One tactic the company is considering: Hiding reply tweets from accounts that have no profile picture, followers, or personal information Costolo was quick to point out to the Times that freedom of speech—and, specifically, allowing pseudonyms—is a cornerstone of the microblog, and one he doesn’t plan to jeopardize.

“The reason we want to allow pseudonyms is there are lots of places in the world where it's the only way you'd be able to speak freely," Costolo told the Times. "The flip side of that is it also emboldens these trolls... How do you make sure you are both emboldening people to speak politically but making it OK to be on the platform and not endure all this hate speech? It's very frustrating."

Costolo’s announcement comes after months of incessant celebrity trolling on the site.

Earlier this week a British actress with Indian roots was forced off Twitter after trolls called her "the ugliest f*cker ever seen" and “not British.” And over the last few months at least three different European soccer players have been the victims of racist tweets and death threats.

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