Reddit is removing several racist communities from its website, as well as other offensive discussion topics, part of an ongoing effort to clean up the most toxic content on its site.

Among those now banned are the subreddits /r/CoonTown and /r/bestofcoontown—as well as others with even more racist names—and also content related to “animated” child pornography, said Steve Huffman, Reddit’s chief executive, in a post on Wednesday.

Reddit is trying to strike a balance between honoring its heritage as a place for free-wheeling free speech while also restricting hateful or harassing content. It’s a tough balance, though, and some of its longtime users have criticized what they see as censorship of the site.

Huffman, who took over as CEO after Ellen Pao resigned last month, said Reddit’s policies are not changing dramatically. But he also introduced a new “quarantining” concept, to restrict access to some controversial communities. Communities whose content would be considered “extremely offensive to the average redditor” will only be viewable to users who explicitly opt in.

When Reddit announced a new anti-harassment policy in May, some users responded angrily, calling the changes vague or confusing. Others said the changes destroy free speech.

But the new Reddit seems focused on cleaning up at least parts of its site, even if that means losing users.

On Wednesday, Huffman said Reddit’s policies will “continue to evolve along with Reddit itself.”