Twitter went down across the world early Tuesday morning and the Internet seriously freaked out.
The cause of the outage was not immediately known, but users soon switched to Instagram and Facebook to vent their frustrations.
The hashtags #TwitterDown and #Twitterpocalypse were trending on both networks within minutes of the outage.
The micro-blogging site's web and mobile services went down at 3:20 a.m., according to the Guardian. It was back up again in Europe around 5:25 a.m., but users in the U.S. still reported it being down.
Visitors to the main Twitter.com website were greeted with the message, "Something is technically wrong. Thanks for noticing -- we're going to fix it up and have things back to normal soon."
Twitter's @Support account told The Independent: "Some users are currently experiencing problems accessing Twitter. We are aware of the issue and working towards a resolution."
It had posted the same message on Twitter, which organizations including The Huffington Post did not see because, well, the site is down.
Twitter's application programming interface, the system that other apps use to communicate with Twitter, also outed. It meant apps such as Echofon were also not receiving updates.
The site suffered numerous outages due to over capacity in its early days, and the appearance of its "fail whale" image became synonymous with the issue.
Heavy investment in Twitter's infrastructure in recent years has mainly curtailed the problem, until now.
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