According to numerous reports, the social media sites were down in many parts of the USA, including the Northeast, as well as overseas.
And while the company acknowledged the problem, it didn't immediately provide answers about the cause or when the service might return to normal.
It further continued that Facebook is working to resolve the issue as soon as possible.
The outage is occurring against a political backdrop of legislators in the USA and beyond considering whether large technology firms - not just Facebook - should be broken up.
Facebook posted to Twitter reassuring users that the site would be back online.
It is thought that Instagram's sister platforms, Facebook and Facebook Messenger may also be experiencing difficulties on Wednesday. Complaints began popping up all over the web around 10 a.m. PT stating that neither Facebook nor Instagram was allowing them to log in.
Photo sharing network Instagram, which is owned by Facebook, is also experiencing loading problems.
We're working to resolve the issue as soon as possible.
The problems were happening across the globe, with large parts of the United States and Europe affected, according to outage tracking website Down Detector. Many report being unable to post, share, or like. Social media users have written in from Canada and Las Vegas to point out the outages in their part of the world.
Facebook and Instagram appeared to be down on Wednesday.
The story is developing...