Facebook, Instagram and WhatsApp were all hit by a similar problem to that which affected Gmail as a global outage affected social media and messaging platforms at midnight yesterday.
The outage affected tens of thousands of users from countries including Britain, the United States, Peru, India and Japan, who reported issues on websites that track problems on social media and messaging websites and applications.
Hong Kong was not spared as users were unable to log into Facebook, and could not post or send pictures on Instagram and WhatsApp.
A Hong Kong user, who works as a social media content producer, said the outage caused problems at her job at about 9am yesterday.
"I wanted to switch to another account to upload content for work, but Facebook takes a million years to get to the tab with the log-out option," she said. "And when I clicked log out, it said something went wrong and wouldn't allow me to."
She also heard her colleague complaining about not being able to upload photos on Instagram for work on Wednesday night.
In addition, the user also faced problems receiving photos on WhatsApp yesterday morning, but could get messages.
However, the problem seemed to be resolved in the afternoon as she was able to receive and upload photos normally on the social media and messaging platforms.
Another Hong Kong user said she could not watched any profiles on Instagram between 1am and 2am. Her friends could not send her any pictures through WhatsApp around 7am.
Instagram began functionally normally after a part outage for hours, but the app of Facebook, its parent company, still appeared to be down for some users across the globe.
Facebook took to Twitter to inform users of the outage: "We're focused on working to resolve the issue as soon as possible, but can confirm that the issue is not related to a DDoS [distributed denial-of-service] attack."
In a DDoS attack, hackers use computer networks they control to send a large number of requests for information from websites so that servers that host them can no longer handle the traffic and the sites become inaccessible.
Instagram announced its services were back to normal at 12.41pm.
"Anddddd . . . we're back," it tweeted along with a GIF image of Oprah Winfrey screaming in excitement.
Reasons for the outage have yet to be announced.
The outage came a day after Google services, including Gmail and Google Drive, experienced a similar issue for hours on Wednesday.