Twitter has introduced more measures aimed at cutting down on the amount of abuse on the platform.
Users will be able to limit what they see from certain types of account, particularly ones with no profile picture or information.
Such accounts are often set up by trolls.
The company said it would act only on accounts that its computer algorithms had thrown up as being abusive.
"Since these tools are new, we will sometimes make mistakes, but know that we are actively working to improve and iterate on them every day," said Ed Ho, Twitter's vice-president of engineering in a blogpost.
The updates are the latest in a series of changes Twitter has implemented in recent months. In February, it said it would make it harder for abusive users to create new accounts, as well as launching a safe search function and collapsing tweet replies deemed abusive so they are hidden from immediate view.
There has been mounting pressure on social media firms to deal with the growth of extremist propaganda, fake news and harassment on their platforms.
Mr Ho added: "We're working to identify accounts as they're engaging in abusive behaviour, even if this behaviour hasn't been reported to us.
"Then we're taking action by limiting certain account functionality for a set amount of time, such as allowing only their followers to see their tweets."
Nick Thomas, an analyst at research firm Ovum, said: "Given that cleaning up Twitter is imperative if it is to attract more advertisers to the site, there is pressure not just to act, but to be seen to act - which may explain why they are making multiple announcements."