The crash occurred at 9:10 p.m. PT and also affected chat hubs AIM and Hipchat and dating app Tinder, which is linked to Facebook. The outage was experienced by much of the U.S., as well as in Australia and New Zealand, according to CNN.
The sites have all since been restored. Facebook and Instagram both returned after about an hour, while Hipchat was down for several hours before returning with service.
The cause was unclear, although hacking group Lizard Squad, which took credit for last month’s PSN and Xbox Live crash, boasted about the outages on Twitter. “Facebook, Instagram, Tinder, AIM, Hipchat #offline #LizardSquad,” read the group’s tweet.
Reps for Facebook and Instagram did not immediately respond to requests for comment.
A tweet showing Facebook’s error message, along with the message from the hackers, can be seen below.
— Saeed Ahmed (@saeed_ahmed) January 27, 2015
— Lizard Squad (@LizardMafia) January 27, 2015