Many of Katy Perry’s 89 million Twitter followers—the most on the platform—were probably intrigued and confused when the pop star tweeted supposed archnemesis Taylor Swift this morning. As it turns out, that tweet—along with several others that were filled with profanity and slurs—was the work of a hacker and quickly deleted.

It appears Katy Perry’s Twitter — with her more than 89 million followers — has been hacked… pic.twitter.com/VmTVKJYGqj — Ryan Parker (@TheRyanParker) May 31, 2016

Those tweets followed one that said “haha follow @sw4ylol #hackersgonnahack.” That account, which is still active, claims to be based in Romania and sent its first tweet on May 29. It also tweeted a link to a SoundCloud song supposedly by Katy Perry, which was taken down after a copyright claim by Universal Music Group.

This incident is yet another reminder that despite the platform’s security measures, no one’s Twitter account is safe—especially if they are a celebrity. Other high-profile Twitters that have been hacked include Justin Bieber, Lea Michele, and Britney Spears—and even the U.S. Central Command.

Earlier this month, Tumblr said it recently found out about a 2013 data breach and required users to reset their passwords. One security researcher estimates it may have affected 65 million users (there’s no indication that data breach and the Katy Perry account hack are related).

TechCrunch has contacted Katy Perry’s reps and Twitter for comment.