South Korea has blamed Chinese hackers for accessing personal data of up to 35 million users on an Internet portal and blogging site.

The Korean Communications Commission revealed details of the hack that affected the Cyworld website, along with a web portal called Nate, both operated by SK Communications, the BBC reports.

The communications regulator said the hackers targeted user’s phone numbers, email addresses, names and other coded information.

South Korean police is probing the case, what has been described as the country’s biggest cyber attack so far.

Analysts note the the motivation for this latest cyber attck is financial gain, rather than political, while the Commission has urged the users of the Nate Internet portal and Cyworld social networking site to change their passwords.

The latest hack follows a string of recent online attacks directed at South Korean government and financial service firms and various internet sites. North Korea has been blamed in some of these hacks.