Social networking site, Facebook has entered into an agreement with security firm Websense to fight against phishing and malwares.

The site will warn users if they are being directed to a malicious website from next week. This indicates that the social network will now check each post in the network posted by millions of its users. Several users were led to virus laden websites through links posted unknowingly on the site by some users.

These sites usually asked users to fill in their passwords or other private data. Facebook already alerts users if they are being taken to an external site but it does not check if the site is safe to visit or poses any threat to the users.

The users clicking on a dangerous link will now see a warning sign whenever it suspects a page poses a threat to the users. The users are then encouraged to return to the the previous page.

"There's over 700 million users on Facebook. As a piece of real estate, it's extremely profitable to be targeted by malware writers,” Websense's Spencer Parker said.