Facebook could be facing a multi-billion dollar fine after a European regulator said it's launching an investigation into the company over failure to protect user privacy.

The Irish Data Protection Commission oversees Facebook's compliance with European law.

It confirmed to CNN on Friday that it had launched a "statutory inquiry" into Facebook after receiving multiple reports of data breaches. 

News of the inquiry came just as Facebook announced that it had exposed photos from nearly seven million users. 

That incident comes after the company announced in September that hackers accessed the personal information of tens of millions of Facebook users. 

It was the biggest security breach in Facebook's history.