Facebook and Instagram have both been hit by severe outages.
Users on both popular platforms have been left unable to load the sites and hundreds of people are unable to access their accounts.
The global outage has affected users in the US, UK, mainland Europe as well as parts of Australia and South America.
This comes less than a day after Facebook Messenger crashed for users around the world.
The outage has left many users seeing only a 'service unavailable' message and others unable to log in or view pictures.
Instagram users were unable to use the web service but the app appeared to be functioning as normal.
Almost half of people (48 per cent) reporting issues with Facebook experienced total blackout and a further 50 per cent reported issues with logging in and picture loading, 35 per cent and 15 per cent respectively.
Users took to rival site Twitter to voice their displeasure at the inability to use the Facebook-owned sites.
One user called Jordan, said: 'So Facebook and Instagram are down? Well, that leaves me with very few ways to communicate with people.#FacebookDown #Instagram.'
Jason Roberts, from Kansas City in the US, added: 'Looks like Facebook is down, you all will have to get some work done when you get to the office.'
A barrage of memes and GIFs were posted on Twitter as disappointed users voiced their frustration.
Facebook confirmed the outage in a brief statement on its page.
It read: 'We are currently experiencing issues that may cause some API requests to take longer or fail unexpectedly.
'We are investigating the issue and working on a resolution.'
Facebook has more than 2.2 billion users worldwide, while Instagram - which is owned by Facebook - has more than one billion active users.
Neither Facebook or Instagram has commented on the cause of the issue.
Similar issues were reported for sister firm Instagram as 46 per cent of people stated issues with the loading of the news feed (46 per cent), logging in (31 per cent) and loading the website (21 per cent).
Yesterday saw Facebook's vast conglomerate was hit with another technical issue as Messenger crashed.
Most users (49 percent) reported they were unable to connect to the server on Monday afternoon.
Many also indicated that they were having trouble receiving messages (28 per cent), while others said they could not log in at all (22 per cent).
The app appears to have crashed shortly after 8pm GMT, with thousands of reports streaming in before 8:30.
Messenger users in Europe were worst affected by the issue Monday afternoon, with a majority of reports coming from the UK, Ireland, Poland, Belgium, and Denmark.
Users in the United States were hit by the outage as well, with most of the issues here popping up along the West Coast.
Just last week, Facebook, WhatsApp and Instagram users around the world were left in a 'total blackout' for nearly an hour after the site crashed early on Nov 12.
Those who attempted to access the desktop site were met with a message saying 'Sorry, something went wrong,' while mobile users were unable to refresh the News Feed.