Instagram went down on Thursday.
Numerous users around the world are reporting issues with the photo-sharing app, with service resuming later that day.
Down Detector, a site that tracks outages, detailed reports of issues across the US, South America, and Europe.
Business Insider reporters in San Francisco, Chicago, and New York were all unable to refresh the app.
The outage didn't seem to be affecting Instagram's parent company, Facebook, but it comes after a spate of outages over the past few months for the embattled social-networking giant.
In a statement prior to Instagram coming back online, a company spokesperson said: "We're aware that some people are having trouble accessing their Instagram accounts. We're working quickly to fix the issue."
This story is developing.