Facebook has discovered a security issue, which could affect up to 50 million users.
A blog post by the social media giant has revealed that attackers found a weakness in Facebook's code regarding its "View As" feature on Tuesday.
Facebook has just started its investigation, and is yet determined if any information was abused:
"Since we’ve only just started our investigation, we have yet to determine whether these accounts were misused or any information accessed."
They continue, "We also don’t know who’s behind these attacks or where they’re based. We’re working hard to better understand these details — and we will update this post when we have more information, or if the facts change"