A massive worldwide global outage has affected millions of people trying to access Facebook, Instagram, and WhatsApp in several countries, including Australia, New Zealand, the UK, and the US.

Facebook users in affected areas have received the message: “Something went wrong. We’re working on it and we’ll get it fixed as soon as we can.”

Instagram has been displaying a 5xx server error message, with the message: “Sorry, this page isn’t available.”

The outage was first reported in Australia and New Zealand at about 2am on Tuesday morning, according to the downdetector.com site.

As the outage continues, it is costing Facebook $160 million every hour the three sites are down, according to NetBlocks.  

“We’re aware that some people are having trouble accessing our apps and products,” Facebook spokesperson Andy Stone said on Twitter.

“We’re working to get things back to normal as quickly as possible, and we apologise for any inconvenience.”

With the three popular sites down, Twitter poked fun at its rivals on their dedicated UK account.

“Hello literally everyone,” they wrote.

The outage has been blamed on a problem with the Domain Name System (DNS), which allows computers to connect to the web server and website users are looking for.

Adam Leon Smith of the Chartered Institute for IT, said: “The outage is caused by changes made to the Facebook network infrastructure. Many of the recent high-profile outages have been caused by similar network-level events.

“It is reported by unidentified Facebook sources on Reddit that the network changes have also prevented engineers from remotely connecting to resolve the issues, delaying resolution.”

Journalist Sheera Frankel said the outage was so severe that Facebook employees have been unable to enter company buildings because their passes were not working.

Image: Facebook, Instagram