Facebook is set to be investigated by the Irish data protection commissioner.

The investigation, which will take place in October, follows 22 complaints by an organisation called Europe versus Facebook regarding how the social networks stores user's personal data. The organisation alleges Facebook holds on to personal information despite saying it has been removed and even tracks users' activity on the web. Furthermore, the group has raised concerns over Facebook's facial recognition feature that automatically identifies users in photos posted to the site.

As Facebook's European headquarters is based in Ireland, the social network must comply with European data protection and privacy laws. The investigation will only look at Facebook's practices outside the US and Canada.

"This audit will examine the subject matter of the complaint but also will be more extensive and will seek to examine Facebook's compliance more generally with Irish data protection law," Irish deputy data protection commissioner, Gary Davis, told the Financial Times.

Facebook could issue a response to the complaints as early as this week. However, it won't be until later this year that the Irish data protection commissioner publishes his report.

"Facebook's European headquarters in Ireland manages the company's compliance with EU data protection law. We are in regular dialogue with the Irish data protection commissioner and we look forward to demonstrating our commitment to the appropriate handling of user data as part of this routine audit," the social network said.

The social network is also facing an investigation in the US by the Federal Trade Commission after a consortium of privacy campaigners, including The Electronic Privacy and Information Centre (EPIC), raised concerns the social network uses cookies to track the web activities of its members even when they're not logged into the network, in a 14-page letter.