Social media meltdown: Facebook, Instagram and WhatsApp down as app crashes for some users

A large-scale glitch led to users being unable to post or view pictures and videos on Facebook, WhatsApp and Instagram on Thursday.

The apparent outage crippled the image-sending capacities of all three apps, though Facebook and WhatsApp seemed to be affected more than Instagram, the Telegraph reported.

It also revealed some of Facebook's hidden wiring and exposed the extent of its AI scanning of images, as users saw pictures replaced by automatically generated text describing their contents.

The text was introduced by Facebook in 2016 to help blind users navigate the service, but is normally only accessible using screen reader software.

"We're aware that some people are having trouble uploading or sending images, videos and other files on our apps. We're sorry for the trouble and are working to get thinks back to normal as quickly as possible," the company said.

The cause of the outage was not immediately clear, nor how many users were effected. Since WhatsApp, Instagram and Facebook are still separate services, the problem may be rooted in a system that provides content or computing power to all three, such as cloud processing.

Many users were susprised to see the AI-generated captions Facebook automatically attaches to all pictures, which say things like "image may contain one person, smiling, outdoors" or "image may contain one person, smiling, glasses, selfie and close-up".

Facebook did not immediately respond to the question of whether it uses any AI image scanning to target adverts.