'I'm gonna knock you out': American Idol auditions cancelled as Nicki Minaj 'threatens and swears' at rival judge Mariah Carey

Nicki Minaj apparently threatened and swore at Mariah Carey during American Idol auditions on Tuesday. Show bosses cancelled filming in Charlotte, North Carolina for the day after a huge blow up between the Starships singer and Mariah, where Nicki fumed she was sick of her co-star's 'f*****g highness'. Their fellow panelists Keith Urban and Randy Jackson were caught in the middle of the row, according to TMZ.A source told the website: '[Nicki said to Mariah] 'I'm gonna knock you out'. 'Nicki added "I told them, I'm not f*****g putting up with her f*****g highness over there.' Producers are now worried about how the pair will manage to work together for the rest of the season. Mariah was said to be unhappy with Nicki joining American Idol because she was worried it would turn the reality TV programme into a 'freak show'.