Twitter has promised that users' personal details are secure following the appearance of a Pastebin post reportedly containing 55,000 accounts' usernames and login details.
The alleged account details were published on five Pastebin pages.
Twitter has since said its opening investigations indicate the details posted are either inaccurate or refer to already blocked spam accounts.
"We've discovered that the list of alleged accounts and passwords found on Pastebin consists of more than 20,000 duplicates, many spam accounts that have already been suspended and many login credentials that do not appear to be linked - that is, the password and username are not actually associated with each other," a spokesperson told V3.
The Twitter representative added the company has also taken protective measures in case any of the unexamined data is accurate.
"We have pushed out password resets to accounts that may have been affected. For those who are concerned that their account may have been compromised, we suggest resetting your passwords," they said.
It is currently unknown which hacker or group is responsible for the attack, though numerous media outlets have since credited it to the hacktivist Anonymous collective.
The reason for the link to Anonymous remains unclear as none of the collectives larger information hubs have issued statements on the attack, instead focusing on its recent attack on Virgin Media.
The breach comes amid a busy week for Twitter, which has asked a New York state judge to dismiss a subpoena that would force it to hand over information about Occupy Wall Street protesters accused of disorderly conduct.
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