A new series of attacks on micro-blogging site Twitter has left some celebrities red-faced.

The company admitted in a blog posting that the attacks occurred early on Monday morning and targeted 33 accounts, including several celebrity Twitter feeds.

Among the victims were US president-elect Barack Obama, pop star Britney Spears and news networks CNN and Fox News.

The hacker posted a fictional update to the Twitter feed for CNN anchorman Rick Sanchez which read: 'I am high on crack right now, might not be coming into work today.'

A similar post was made to the Fox News blog claiming that anchorman Bill O'Reilly was gay, while the Spears feed sported a vulgar message claiming to be from the pop singer. Obama's feed included a link to a survey site which pays users for traffic referrals.

Twitter said that as of early afternoon US Pacific time, all of the hacked accounts had been secured and any posts made by the attacker had been removed.

The postings appeared shortly after news broke of a phishing attack on Twitter users. The company said that this latest series of hacks is not believed to be related to the phishing operation.

"These accounts were compromised by an individual who hacked into some of the tools our support team uses to help people do things like edit the email address associated with their Twitter account when they can't remember or get stuck," the company explained.

As a result of the attack, Twitter has taken down the compromised support tools until a fix can be made to prevent future attacks.

Users are still being advised to steer clear of unsolicited messages, and ignore any outside site that asks for Twitter log-in details.