Steven Tyler - Steven Tyler Swears On American Idol

Complimenting Idol finalist Casey Abrams on his performance, the Aerosmith star stunned fellow judges Jennifer Lopez and Randy Jackson with his foul mouth.

Tyler, who has a history of using salty language on the hit show, said, "There's millions of people in America that are really angry because you p**s them off because you're so f**king good."

Even Abrams was shocked, covering his mouth as judge Jackson jumped up from his chair and said, "What is going on?"

Host Ryan Seacrest then took the stage and said, "Whoa, the wheels have fallen off this programme."

The show went to a commercial break and when it returned, Tyler had his mouth taped shut.

He ripped the tape off, and stated, "You can't keep me quiet."