Millions of Instagram users across the world have been left in the dark after a sudden outage took the service offline.

Reports of Instagram being inaccessible began arriving at 7:20 pm Eastern time in the US, but the outage map is showing failures in both Americas, Europe and Australia, according to the website DownDetector.

Though the Instagram app would open for some users, it refused to refresh the feed, send or receive messages, or post images.

Users flocked to other social media, such as Twitter, sharing the stories of their woe under the hashtag #Instagramdown.

Instagram is down for four minutes and the world loses its mind. — NICHOLAS MEGALIS (@nicholasmegalis) January 29, 2019

"We're aware of an issue causing Instagram to be down for some users right now," an Instagram spokeswoman said. "We're working quickly to fix this."

Instagram, which is owned by Facebook, gave no explanation for previous two major outages, in November and October last year.

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