Business social networking site LinkedIn has confirmed reports that millions of its user’s passwords were leaked on the Internet earlier this week.

The Mountain View-based company said that passwords for 6.5 million of its 160 million member were breached.

In a blog post on Thursday, LinkedIn Director Vicente Silveira said “to the best of our knowledge, no email logins associated with the passwords have been published, nor have we received any verified reports of unauthorized access to any member’s account as a result of this event.”

The company has suggested that all members change their passwords as they continue to work with law enforcement to figure out how the breach occurred.

The question becomes how other social networking sites will react to the problem. More and more, I am seeing people hacked on Twitter (the posts about weight loss programs are usually a good bet that you’ve been hacked). But will this be an ongoing problem for not only LinkedIn, but for Twitter, Facebook and the like in the near future? Only time will tell.