Facebook on May 15 was blocking links to bogus web sites set up to look like the home page of the popular online social network in a "phishing" attack by hackers, AFP reports. "We’re aware of the attack and are already blocking links to these new phishing sites from being shared on Facebook," the Palo Alto, California, company said in a statement. "We’re also cleaning up phony messages and wall posts and resetting the passwords of affected users." Facebook did not say how many of the 200 million users of the social network had been affected in the latest hacker attack. An unknown number of Facebook users received a message on May 14 from a friend’s account urging them to visit web sites such as "151.im." The sites were realistic-looking replicas of the social network’s log-in page but were actually controlled by the hackers. The bogus page would capture password information when a user logged in. Facebook advises users to avoid messages, posts, or links asking for log-in information and to always make certain they are visiting its legitimate address, facebook.com…