WASHINGTON – Facebook’s security team has been working to remove an influx of pornographic and violent spam messages that have been flooding users’ news feeds over the past couple of days.

Facebook spokesman Frederic Wolens told CNN that the social network had identified the cause of the messages and “have eliminated most of the spam” coming from the hack.

Reports began to surface over the weekend that users were seeing disturbing images posted on their feeds, including photos of Justin Bieber in sexual situations and pictures of abused animals.

Graham Cluley, a consultant with web security firm Sophos, wrote Tuesday that the hack caused many Facebook users to cancel their accounts.

“What’s clear….is that mischief-makers are upsetting many Facebook users and making the social networking site far from a family-friendly place,” Cluley wrote.

“It’s precisely this kind of problem which is likely to drive people away from the site. Facebook needs to get a handle on this problem quickly, and prevent it from happening on such a scale again.”

Gawker speculated earlier this week that the hack may be the work of Anonymous, which recently claimed to be working on a “Guy Fawkes virus.”

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