New Reddit CEO Steve Huffman announced today that the site has updated its content policy, which introduces a change that will hide subreddits with “objectionable content” to anyone who doesn’t explicitly opt-in to view them. The updated policy has also put an outright ban on a number of communities, including several racist subreddits.

The “Quarantine” policy will be used on communities that “would be considered extremely offensive to the average redditor,” according to Huffman. It’s not yet clear which subreddits will be affected, but the CEO said that the moderators would be notified. Quarantined sections of the site will generate no revenue, either through ads or through Reddit Gold, its premium membership service.

The Reddit co-founder said that those communities banned completely were chosen because they “exist solely to annoy other redditors, prevent us from improving Reddit, and generally make Reddit worse for everyone else.” Six racist discussion forums, including the notorious /r/CoonTown, along with a community dedicated to posting and discussing animations of child pornography, have been shut down.

Huffman said the racist communities were banned for their behavior, not their content. “We didn’t ban them for being racist. We banned them because we have to spend a disproportionate amount of time dealing with them. If we want to improve Reddit, we need more people, but [Coontown]’s existence and popularity has also made recruiting here more difficult.”

Some redditors see the updated policy as the platform clamping down on free speech, while others claim the new measures don’t go far enough, and that while certain subreddits are being banned, other controversial communities continue to exist.

This is not the first time Reddit has banned sections of the site following policy changes. Former CEO Ellen Pao implemented an anti-harassment policy in May after a company survey found that some users shied away from the site and wouldn't recommend it to other people because of abusive posts and content. This led to the shutting down of five communities, resulting in certain redditors turning their ire towards Pao. She resigned as CEO last month amid criticism over the way she was running the company.