A major internet outage knocked tens of thousands of websites and other platforms offline or made them difficult to access on Thursday, including Airbnb, TikTok, the Playstation Network, Steam, Southwest Airlines, Delta Airlines, Ally Bank, and Fidelity.

The problem reportedly originated with Akamai, a leading cloud computing platform used by many large companies around the world to provide DNS and other services.

Via Engadget:

Based on Twitter reports, the source of the problem is Akamai, one of the largest content delivery networks in the world. “We are aware of an emerging issue with the Edge DNS service,” the company said in an update it posted on its website at 12:09PM ET. “We are actively investigating the issue.” As of the writing of this article, Akamai has not said what’s causing the issue.

DNS outages aren’t uncommon, but it’s not often they make large parts of the internet inaccessible. In recent memory, one of the most disruptive occurred in 2016 when a teen used the infamous Mirai malware to build out a botnet and carry out a series of distributed denial of service attacks against Dyn, one of the largest DNS providers in the US. The attacks made it so that people in the US and parts of Europe couldn’t access websites like Amazon, GitHub, PayPal and Reddit for almost an entire day. The individual behind the Dyn cyberattack eventually pleaded guilty for what they did, but not before a variety of groups like Anonymous and New World Hackers claimed responsibility.

As of 1:00 p.m. ET, Akamai said the issue had been fixed, and many of the websites and platforms affected are now accessible again.

Allum Bokhari is the senior technology correspondent at Breitbart News. He is the author of #DELETED: Big Tech’s Battle to Erase the Trump Movement and Steal The Election.