Update: services are back up after a one hour outage, and hacker group Lizard Squad has claimed responsibility, see updates further down.

It’s not just you: Facebook Inc. and Instagram services are down early Tuesday morning U.S. EST, and were inaccessible from anywhere on the globe.

The site Facebook Is Down confirmed the outage.

We are not sure at this stage what has caused the outage; the only official word has been a Twitter post from Instagram saying that “We’re aware of an outage affecting Instagram and are working on a fix. Thank you for your patience.”

Gadget blog Engadget reported that the outage may be more widespread than Facebook and Instagram alone, suggesting that there may be a serious data center outage somewhere.

Facebook, Instagram, Tinder, AIM, and Hipchat all appear to be offline. We’ll keep you updated when we hear more.

— Engadget (@engadget) January 27, 2015

The news of Facebook being down caused the hashtag #Facebookdown to trend globally on Twitter.

911 operators in America must be taking a lot of calls from people telling them about #facebookdown.

— Erk (@erkpod) January 27, 2015

Update 2:10am EST: TechCrunch reports that the outage at Tinder, AIM and others may be related to the fact that those apps use Facebook’s login services to operate. Potentially then the flow on affects far more than the named apps.

Update 2:17am EST: Facebook and Instagram are both back up at the time of writing. There are some reports that the outage may be related to the “snowmaggedon” snow storm on the East Coast, but we find this unlikely given Facebook’s data centers are on the West Coast.

Update 3:20am EST: The notorious Lizard Squad has claimed responsibility

https://twitter.com/LizardMafia/status/559963134006292481

There’s no confirmation currently but reports are suggesting that the sites went down due to a large DDoS attack, with the following image doing the rounds allegedly showing how it took place.

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