Social news site Reddit has launched an anti-harassment policy that allows it to ban users who bully others.
In a blogpost, the site - known for its liberal attitude towards free speech and anonymity - said it was "unhappy with harassing behaviour".
Users who believe they are being bullied will be able to email Reddit and report it.
But some users complained that the policy is vague and not in keeping with Reddit's promotion of free speech.
The site announced the changes, for which it has been preparing for six months, in a blogpost on Thursday.
"We've seen many conversations devolve into attacks against individuals," the San Francisco company wrote, adding that it is also seeing more and different types of harassment than in the past.
For example, some users are harassing people across platforms and posting links on Reddit to private information on other sites, it said.
It added that it defines harassment as "systematic and/or continued actions to torment or demean someone in a way that would make a reasonable person (1) conclude that reddit is not a safe platform to express their ideas or participate in the conversation, or (2) fear for their safety or the safety of those around them".
But, in comments posted on the site, users expressed dissatisfaction with the plan.