According to a story on the Guardian site, a report from the Belgian data protection agency has revealed that Facebook tracks the computers of users without their consent, regardless of whether they are logged in to Facebook, are registered users of the site, or have explicitly opted out in Europe.

The report, carried out by researchers at the Centre of Interdisciplinary Law and ICT (ICRI) and the Computer Security and Industrial Cryptography department (Cosic) at the University of Leuven, and the media, information and telecommunication department (Smit) at Vrije Universiteit Brussels, was commissioned following a draft report that revealed Facebook’s privacy policy breaches European law.

The issue apparently relates to Facebook’s use of its social plugins, including the ‘Like’ button included on over 13m sites worldwide. If a user visits a third party site that carries one of these plugins, it detects and sends tracking cookies back to Facebook, regardless of whether the user interacts with the Like button.

EU privacy law states that prior consent must be obtained before issuing a cookie or performing tracking, unless it is necessary for either the networking required to connect to the service or to deliver a service specifically requested by the user.