Facebook has been targeted by phishers again, with several users tricked into handing over their log-in and password details.
According to reports, the hackers broke into Facebook accounts before sending thousands of e-mails to friends.
The e-mails contained links to fake sites that looked like the Facebook homepage, where victims were directed to log in, giving their details to the hackers.
A spokesman told reporters the company is blocking links to the phishing sites, cleaning up fake messages and Wall posts and resetting the passwords of affected users. The number of victims is not known.
Social networking sites are increasingly being targeted by criminals looking to steal personal information or spread malware. According to security outfit Sophos, one in five people say they have been on the receiving end of a phishing attack via the likes of Twitter and Facebook.