BEIJING, March 15 -- Industrial standards for China's Internet advertising went into effect on Saturday as concerns rise over users' information security.

The standards, created by the China Internet Association, require that the collection, use, transfer and sharing of user information should stick to mutual agreements and abide by laws and regulations.

Websites are required to make clear to users when they are collecting and using information and notify users in a timely manner for privacy protection. Sensitive information can only be collected after agreement by users, according to the standards.

The association said that, unlike traditional advertising, online advertisers can target special groups of users based on their online behaviors, which can be recorded and analyzed, stirring privacy concerns.

Mainstream Internet companies, advertising firms, and third-party companies have also participated in creating the standards, according to the association.