A spokesperson added, "As a result, many people had difficulty accessing our apps and services".
No cause has been given but Facebook said it wasn't a distributed denial of service or cyberattack.
Instagram users began reporting problems with the photo-sharing app shortly after Facebook seemed to go haywire.
This is an important draw for people concerned with their privacy online, particularly in light of the fact that Facebook, Inc.is reportedly now under criminal investigation for secret data sharing deals. Facebook's ad platform, Facebook Ad Manager, was also down.
Chiefs set to trade Ford to Niners, source says
According to ESPN, San Francisco will give Ford a five-year, $87.5 million deal once the trade is completed. Rapoport was the first to report that the 49ers were "deep in talks" with the Chiefs for Ford.
Facebook's shares fell almost two per cent in morning trading on Thursday.
Facebook claimed in June 2018 that it provided dozens of tech companies with special access to user data after publicly saying it restricted such access in 2015.
A spokesman for the social network said the company was cooperating with investigators in multiple federal probes, without addressing the grand jury inquiry specifically.
The social network said on Thursday that changes to a server configuration were to blame. Facebook's desktop platforms and apps were affected in parts of the US, including the East and West Coast, as well as parts of Europe and elsewhere. "We're very sorry for the inconvenience and appreciate everyone's patience".
The Menlo Park, California-based company, which gets a vast majority of its revenue from advertising, told Bloomberg that it was still investigating the overall impact "including the possibility of refunds for advertisers".