Twitter has confirmed the existence of a bug that allowed users to force others to follow their messages.
The flaw let Twitter users add followers simply by typing 'accept' followed by a twitter name.
This would have allowed spammers to build huge mailing lists if the process had been automated, and there are some reports of celebrities being signed up as followers without their consent.
News of the bug spread rapidly online, causing a spike in its use, and Twitter moved quickly to fix the problem. However, in doing so the company caused a large number of users to lose all friends and followers.
"We identified and resolved a bug that permitted a user to 'force' other users to follow them. We are now working to rollback all abuse of the bug that took place," the company said in a blog post.
"Follower/following numbers are currently at zero, and this too should shortly be resolved."
Twitter is now working to restore previous friend and follower settings, and has warned users that they should remove any unknown followers from their list.
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