Facebook, Facebook Messenger, Instagram and WhatsApp are all currently down, with users reporting widespread issues with the services.
According to website DownDetector, the problems on the four sites - which are all owned by Facebook - started at around 4.44pm, and are said to be affecting users globally.
Facebook has since issued a statement over on Twitter, saying it was working to get things 'back to normal'.
It said: "We're aware that some people are having trouble accessing our apps and products.
"We're working to get things back to normal as quickly as possible, and we apologize for any inconvenience."
We're aware that some people are having trouble accessing our apps and products. We're working to get things back to normal as quickly as possible, and we apologize for any inconvenience.
- Facebook (@Facebook) October 4, 2021
TechCrunch reports that, when navigating to the respective websites, a server error is appearing.
"Instagram shows a '5xx server error', which indicates that this is an issue with Facebook's servers," the outlet says.
"Users are also unable to send messages or load new content on the mobile apps for these platforms. Even Oculus, Facebook's virtual reality platform, is experiencing outages, according to a tweet the platform posted.
"It appears that the outage is caused by a DNS (domain name server) fail - this is the naming structure that forms the web's infrastructure. So, if you try to navigate to facebook.com right now, the internet won't know where to find facebook.com."
Naturally, with the four popular social media platforms all unavailable, many people jumped onto Twitter to express their frustration - with many jumping at the chance to slip in a Squid Game reference:
WhatsApp, Insta and Facebook down
Twitter : pic.twitter.com/o3cBXqog6C
- (@itsjustdarryll) October 4, 2021
Facebook, Instagram and WhatsApp have been eliminated!#Facebookdown #Instagramdown #whatsappdown pic.twitter.com/dZSlFipx2h
- Jawad (@Qazijawadu) October 4, 2021
WhatsApp,Facebook,and Instagram down again,the world right now switching to twitter#WhatsApp #facebookdown #Instagram pic.twitter.com/SUZzhZTBEj
- Muhammad Kamran (@Muhammadkami02) October 4, 2021
Others went for more classic memes:
Whatsapp, Facebook and Instagram down again.
Thank you @Twitter :grinning:#WhatsApp #facebookdown pic.twitter.com/GCuJtIq4m2
- ســـــدرہ:dizzy: (@Sidra_VOIk) October 4, 2021
Others were discussing the issues over on DownDetector, as well, with one joking: "Oh well, may aswell print selfies of myself and post them through everyones letter box asking them to 'like' it."
Another quipped: "Is this because the servers are running out of petrol?"
A third said: "Down Detector is now the new Facebook."