Illustration by Alex Castro

Facebook had problems loading images, videos, and other data across its apps today, leaving some people unable to load photos in the Facebook News Feed, view stories on Instagram, or send messages in WhatsApp. Facebook said earlier today it was aware of the issues and was “working to get things back to normal as quickly as possible.” It blamed the outage on an error that was triggered during a “routine maintenance operation.”

As of 7:49PM ET, Facebook posted a message to its official Twitter account saying the “issue has since been resolved and we should be back at 100 percent for everyone. We’re sorry for any inconvenience.” Instagram similarly said its issues were more or less resolved, too.

The issues started around 8AM ET and began slowly clearing up after a couple hours, according to DownDetector, which monitors website and app issues. The errors aren’t affecting all images; many pictures on Facebook and Instagram still load, but others are appearing blank. DownDetector has also received reports of people being unable to load messages in Facebook Messenger.

The outage persisted through mid-day, with Facebook releasing a second statement, where it apologized “for any inconvenience.” Facebook’s platform status website still lists a “partial outage,” with a note saying that the company is “working on a fix that will go out shortly.”

Apps and websites are always going to experience occasional disruptions due to the complexity of services they’re offering. But even when they’re brief, they can become a real problem due to the huge number of users many of these services have. A Facebook outage affects a suite of popular apps, and those apps collectively have billions of users who rely on them. That’s a big deal when those services have become critical for businessand communications, and every hour they’re offline or acting strange can mean real inconveniences or lost money.