Facebook, Instagram and WhatsApp are now back online, following an outage of more than six hours.
Almost three billion people were affected by the outages worldwide – and reportedly $50bn was wiped off of Facebook’s value.
The sites went down at around 5pm on Monday, leaving users without access for around six hours.
A statement from Facebook said: “Our engineering teams have learned that configuration changes on the backbone routers that coordinate network traffic between our data centres caused issues that interrupted this communication. This disruption to network traffic had a cascading effect on the way our data centres communicate, bringing our services to a halt.
“Our services are now back online and we’re actively working to fully return them to regular operations. We want to make clear at this time we believe the root cause of this outage was a faulty configuration change. We also have no evidence that user data was compromised as a result of this downtime.”
The company said that the underlying cause of the outage also impacted many of the internal tools and systems Facebook uses in its day-to-day operations, complicating the company’s attempts to quickly diagnose and resolve the problem.