The tech firm said the temporary outage was caused by a "routine test."
Did you have trouble accessing your Facebook feed? If so, you aren't alone.
Facebook was down this morning in the US, as well as other parts of the world. The outage, caused by a test the social network was conducting, lasted about 40 minutes.
"Earlier today, a routine test caused users to have trouble accessing or posting to all Facebook services including WhatsApp and Instagram," a Facebook spokesperson said in a statement. "We quickly investigated and restored access for everyone. We're sorry for the inconvenience."
Facebook declined to elaborate on what the company was testing on Monday or whether an outage was expected.
Users ran into various error messages when trying to access the Facebook app, website and Facebook Messenger. Several people at CNET also experienced problems.
Affected areas include the east coast of the US, Mexico, Brazil and Peru, according to Down Detector.
People on Twitter also reported issues.
Update, 10:50 a.m. PT: Facebook is working again for people who previously reported issues.
Update, 2:05 p.m. PT: Added statement from Facebook spokesperson.
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