LinkedIn is looking into the possibility that 6.5 million passwords of its users have been leaked online.

Hackers have uploaded a file containing encrypted passwords of nearly 6.5 million LinkedIn users, according to security firm Sophos. The business social networking site has not confirmed the breach yet while hackers are working on cracking the passwords.

See also: How to change a LinkedIn password.

LinkedIn said on Twitter: "Our team is currently looking into reports of stolen passwords. Stay tuned for more."

Sophos has confirmed that, in part, the uploaded file does contain passwords to LinkedIn. It said: "Although the data which has been released so far does not include associated email addresses, it is reasonable to assume that such information may be in the hands of the criminals."

The advice from Sophos and ourselves is to change your password for LinkedIn as a precaution if nothing else.