The social networking sites Facebook, Instagram and the messaging application WhatsApp were suddenly disrupted on Monday, with users around the world reporting their inability to access them, according to Reuters.

And the website "Downdetector", which specializes in tracking technical failures, published a tweet stating that these sites were down.

The three applications are owned by Facebook and operate on a common infrastructure.

According to the information that these sites stopped working completely. Other services that are part of these apps, such as Facebook Workplace, have also been discontinued.

The outage comes a day after a whistleblower appeared on US television to reveal her identity after leaking a trove of documents to authorities, alleging that Facebook knows that its products fuel hate and harm children's mental health.

Data expert Frances Hogan, 37, has worked at companies including Google and Pinterest, but said in an interview with CBS's "60 Minutes" news program that Facebook was "much worse" than anything she's seen before.

Facebook did not immediately respond to a request for comment on the outage.