Elon Musk’s X has been hit by three waves of outages since this morning, which the billionaire said was due to a cyberattack.

Tens of thousands of users reported issues using Musk’s platform, formerly known as Twitter, after what appeared to be an earlier outage.

U.S. officials have not determined who was behind an apparent cyberattack on the social media site X that limited access to the platform for thousands of users.