Nicki Minaj and Mariah Carey Fighting on America Idol

Nicki Minaj derailed the "American Idol" auditions on Tuesday, after swearing at Mariah Carey and threatening, "I'm gonna knock you out" .

In the footage, obtained by TMZ, Nicki is clearly furious ... shouting, "I told them I'm not fuckin' putting up with her fuckin' highness over there."

Sources say Nicki later threatened to "knock out" Mariah Carey but she said it before the video starts.

It all went down while the two were sitting at the judge's table with Keith Urban sitting in between them and Randy Jackson sitting on the far end, next to Mariah.

Tthe whole thing exploded over a disagreement over a contestant's performance.

producers ended the auditions for the day so the two judges could cool down.  We've confirmed that happened.

Source : TMZ