Facebook and two of its subsidiaries, Instagram and WhatsApp, are reeling from a simultaneous outage that took out all their three social media sites in an incident Facebook denies is a massive Distributed Denial-of-Service (DDoS) attack.

As of 5:00 p.m. ET today, Facebook users worldwide were still reporting issues loading and posting on Facebook, Instagram and WhatsApp using their computers and mobile phones. Facebook has acknowledged issues with its core app, Instagram and WhatsApp.

This outage is now more severe than the one in 2013 that also took down several websites. This glitch lasted a few minutes but impacted an array of websites including The New York Times and CNN. Facebook’s remote log-in feature was determined to be the cause of this glitch.

Facebook hasn’t given a reason for today’s outage, but says this simultaneous glitch isn’t a DDoS hit. In a DDoS attack, hackers overwhelm a targeted site by flooding it with fake traffic.

Facebook acknowledged the outage in a tweet Wednesday, saying, “We’re aware that some people are currently having trouble accessing the Facebook family of apps. We’re working to resolve the issue as soon as possible but can confirm that the issue is not related to a DDoS attack.”

Reports of problems with Facebook peaked at over 11,000 worldwide, said Downdetector, a website where users can report problems on apps and websites. Users reported a host of problems such as being unable to load the site at all and not being able to post comments.

Facebook users posted Twitter screenshots showing error messages when they tried to load the three apps. Some users’ saw an onscreen message saying “Account Temporarily Unavailable.”

DownDetector said the outages are mainly in New England, Texas, Seattle, Washington, parts of Latin America (including Peru), the United Kingdom, the Philippines and India.

App In this photo illustration, an Instagram photo of the Facebook website app is seen. Facebook was hit by an inexplicable outage that also took down WhatsApp and Instagram. Photo: Justin Sullivan/Getty Images

Users are now complaining Oculus is also down. One user said he can’t log in to any multiplayer games purchased through the Oculus store. He also can’t access his Oculus Home environments. Other users complained they’re unable to buy games from the Oculus store.

Using Facebook to sign into Tinder or Spotify is also futile. Doing so leads to the error message saying this feature isn’t available right now.

Tech analysts noted Facebook previously experienced an outage of its tool for advertisers in November 2018. At this time, marketers were trying to place ads for the Black Friday and Cyber Monday sales events.