SOCIAL networks Facebook and Instagram went down for an hour on Tuesday afternoon.
While hacking group Lizard Squad claimed responsibility for the hack, Facebook said that its engineers had caused the problem itself.
A Facebook spokesperson said: "Earlier today many people had trouble accessing Facebook and Instagram.
"This was not the result of a third party attack but instead occurred after we introduced a change that affected our configuration systems. We moved quickly to fix the problem, and both services are back to 100% for everyone."
The company said that the outage was not connected to Lizard Squad, the snowstorm in the US, or any other external group.
Users worldwide experienced the issue, both on the web and via mobile apps, however Facebook-owned mobile messaging service WhatsApp was running as usual. There were reports that matchmaking app Tinder and Hipchat instant messaging were also down.
A message on Facebook said: "Sorry, something went wrong. We're working on it and we'll get it fixed as soon as we can."
Services were down for about 50 minutes.
Facebook last went down in September, where outages occurred twice in the same month.
After one hour, all services are online again.
Black hat hacking group the Lizard Squad have hinted that they have something to do with the outage but this is yet to be confirmed by official sources at Facebook, Instagram, Hipchat or Tinder.
Yesterday they took credit for the hacking of the Malaysia Airlines website.
But Facebook and Instagram denied the outage was a hack, instead blaming a "systems change" for the problem.
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