"For a brief period of time, some internal prototypes were made public to a number of people externally," a spokeswoman for the company said. "As a result, we took the site down for a few minutes. It's back up, and we apologize for the inconvenience."
Messages on Twitter and technology blogs put the outage at about 15 minutes, around 1.30 pm U.S. Pacific time.
Downtime for Facebook, which is relatively rare, not only affects users, but can hurt other sites and advertisers dependent on traffic from links in Facebook.
Facebook Down December 16
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