Katy Perry's Twitter account was hacked on Monday and the hackers posted some nasty and vulgar tweets, including one referring to her feud with fellow singer Taylor Swift, reported a website.

Katy Perry
Katy Perry

At around 12.30 pm, the songtress retweeted Hillary Clinton's Memorial Day message along with her message and an American flag emoji.

Five hours later, the hackers gained access to her account and posted a series of random tweets on her timeline. One of them was referring to her longstanding feud with Swift. They wrote, "Miss you baby," while tagging the Shake It Off hitmaker's account.

All of the tweets were deleted from the Dark Horse singer's account 15 minutes after they were posted. However, Twitter account @sw4ylol, which allegedly belongs to the hackers, shared Katy's new song called Witness 1.3.

The official account later posted a screenshot of an e-mail from the music sharing site, announcing they had removed the track under a copyright claim by Universal Music Group.