Facebook and its Instagram and WhatsApp platforms suffered a worldwide outage that has extended for more than three hours on Monday. Facebook's internal systems used by employees also went down. Service had still not been restored as of 2 p.m.
The company did not say what might be causing the outage, which began around 8:40 a.m. PT. Websites and apps often suffer outages of varying size and duration, but hours-long global disruptions are rare.
"This is epic," said Doug Madory, director of internet analysis for Kentik Inc. The last major internet outage, which knocked many of the world's top websites offline in June, lasted less than an hour. The stricken content-delivery company in that case, Fastly, blamed it on a software bug triggered by a customer who changed a setting.
Facebook's only public comment so far was a tweet in which it acknowledged that "some people are having trouble accessing [the] Facebook app" and that it was working on restoring access. Regarding the internal failures, Instagram head Adam Mosseri tweeted that it feels like a "snow day."
So many people are reliant on Facebook, WhatsApp or Instagram as a primary mode of communication that losing access for so long can make them vulnerable to criminals taking advantage of the outage, said Rachel Tobac, a hacker and CEO of SocialProof Security.