Twitter has suspended its verified-profile scheme and described it as "broken", following complaints over the type of accounts being verified.
Typically, prominent people, including musicians, journalists and company executives, get a blue icon on their profile after proving their identity.
However, some far-right and white-supremacist accounts have now also been verified.
Twitter founder Jack Dorsey said the scheme would now be "reconsidered".
We should’ve communicated faster on this (yesterday): our agents have been following our verification policy correctly, but we realized some time ago the system is broken and needs to be reconsidered. And we failed by not doing anything about it. Working now to fix faster. https://t.co/wVbfYJntHj— jack (@jack) November 9, 2017
In a statement, the company said: "Verification was meant to authenticate identity and voice, but it is interpreted as an endorsement or an indicator of importance.
"We recognise that we have created this confusion and need to resolve it."
The company said no further "general" accounts would be verified, while it worked on a fix.
Twitter has been making a series of changes to address abuse and harassment on the social network.
Last week, it published a rewritten version of its rules, which it said would make them easier to understand.