New York (CNN Business)Facebook announced on Friday that the social network had exposed the private photos of millions of users without their permission.
The company said a bug recently allowed third-party app developers to access photos people may not have shared publicly. Facebook believes as many as 6.8 million users could be affected.
The Irish Data Protection Commission, the body that oversees Facebook's compliance with European regulations, said on Friday that it had launched a "statutory inquiry" into Facebook as a result of multiple breaches the company had informed them about this year.
Photos that users started to upload to Facebook but did not post could have been accessed, along with images posted to Facebook Stories,Tomer Bar, an engineering director at Facebook, wrote in a blog post.
"We're sorry this happened," he added.