Facebook: Sophisticated hackers attack us!

REPUBLIKA.CO.ID, SAN FRANCISCO/LOS ANGELES - Facebook Inc said on Friday hackers had infiltrated some of its employees' laptops in recent weeks, making the world's No.1 social network the latest victim of a wave of cyber attacks, many of which have been traced to China.

It said none of its users' data was compromised in the attack, which occurred after a handful of employees visited a website last month that infected their machines with so-called malware, according to a post on Facebook's official blog released just before the three-day US President's Day weekend.

"As soon as we discovered the presence of the malware, we remediated all infected machines, informed law enforcement, and began a significant investigation that continues to this day," Facebook said.

It was not immediately clear why Facebook waited until now to announce the incident. Facebook declined to comment on the reason or the origin of the attack. A security expert at another company with knowledge of the matter said he was told the Facebook attack appeared to have originated in China.

Infiltrated

The attack on Facebook, which says it has more than 1 billion members, underscores the growing threat of cyberattacks aimed at a broad variety of targets. Twitter, the microblogging social network, said earlier this month it had been hacked and that about 250,000 user accounts were potentially compromised, with attackers gaining access to information, including user names and email addresses.

Newspaper websites, including those of The New York Times , The Washington Post and The Wall Street Journal, have also been infiltrated. Those attacks were attributed by the news organizations to Chinese hackers targeting coverage of China.

Earlier this week, US President Barack Obama issued an executive order seeking better protection of the country's critical infrastructure from cyber attacks.

Facebook noted in its blog post that it was not alone in the attack, and that "others were attacked and infiltrated recently as well," although it did not specify who.

The Federal Bureau of Investigation declined to comment, while the US Department of Homeland Security did not immediately return a call seeking comment. Another fear for such a popular website is that hackers could use central controls to infect wide swathes of its user base at once.

In January 2010, Google reported it had been penetrated via a "zero-day" flaw in an older version of the Internet Explorer Web browser. The attackers were seeking source code and were also interested in Chinese dissidents. Google reduced its operations in China as a result.