Facebook users across Europe were left without access to the site after technical issues knocked it offline on Wednesday morning.
The firm said it has now sorted the problem and apologised to users, but didn't provide any information on what had caused the incident.
"Today we experienced technical difficulties causing the site to be unavailable for a number of users in Europe," a spokesperson said.
"The issue has been resolved and everyone should now have access to Facebook. We apologise for any inconvenience."
V3 asked Facebook for more information but the firm declined to comment.
Twitter users expressed their surprise and disappointment at the outage, with hashtags such as #facebookdown and #fbdown trending in several locations.
The scale of the incident is likely to have meant that millions of users were left without access, with Europe one of the core regions for the site.
The incident is a rare blip for firm as it heads towards its highly-anticipated floatation on the stock market, which could see the firm valued as high as $100bn, with the site likely to hit one billion users by this date.
It's not the first time it has suffered an outage, though, with an incident in September 2010 knocking the site offline for over two hours, which the firm said was the result of improper error handling.
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