Facebook, Instagram, WhatsApp and Facebook Messenger which all went down on Monday afternoon with users worldwide reporting the crashes, have now been restored.
The sites were restored around 10.45pm after about six hours of crash, cutting off billions of users around the world.
The online services all share an infrastructure and are owned by Facebook, which is owned by American billionaire Mark Zuckerberg.
The crash started around 16:41BST, according to the website Downdetector. While just two problems were reported at 16:26, the site says, this had jumped to more than 27,000 just fifteen minutes later.
According to The National, users attempting to access Facebook on their browser were shown a blank error page, while those using WhatsApp or Instagram mobile apps were able to view existing content, but nothing new has loaded.
“We’re aware that some people are having trouble accessing Facebook app. We’re working to get things back to normal as quickly as possible, and we apologize for any inconvenience,” Facebook had said via @facebookapp
Posting on Twitter, which has not seen any issues, the Facebook app had said it was aware of outages affecting “some people”.