Mariah Carey and Nicki Minaj catfight reached boiling point when Nicki was caught on camera hurling a torrent of abuse at fellow American Idol judge Mariah.

And, with Mariah Carey said to be in fear of her safety on the show, it has emerged that Nicki Minaj was “supremely disrespectful” to Mariah two years before she exploded on the Idol set earlier this week.

According to TMZ, Nicki Minaj was allegedly “rude” to Mariah Carey on the set of the music video Up Out My Face back in 2010.

The video shows Mariah Carey and Nicki Minaj happily performing the song together, dressed in identical nurses outfits and red dresses, giggling away and drinking champagne.

But it was a different story off set, according to TMZ, with B. Scott, who appeared alongside Mariah Carey in the video, alleging that: “Nicki was making faces at her [Mariah] laced with rude comments under her breath.

“Mariah went out of her way to be nice to Nicki and make her comfortable,” B. Scott added, with the website reporting that Mariah Carey felt like she was helping launch Nicki Minaj’s career by appearing in the video.”

TMZ claims B. Scott told Mariah Carey what was going on with the Super Bass singer, but says: “Mariah decided not to confront Nicki and acted as if nothing had happened.”

However, a source close to Nicki Minaj said: “Scott works as Mariah’s stunt double and of course he would say things like that. He’s worked for her for years.”

Meanwhile, B. Scott told the website that he stays in touch with Mariah Carey and spoke with her on Thursday night.

He said that Mariah Carey “wants to bury the hatchet with Nicki on American Idol and focus on the contestants”.

Meanwhile, former American Idol judge Steven Tyler seemed a little skeptical about the row when a TMZ cameraman caught him outside an LA restaurant last night and asked him if the Mariah Carey, Nicki Minaj feud was “bs”.

“Of course, are you kidding?” he replied.

Earlier this week, it was reported that Mariah Carey was keen to hire extra security after Nicki Minaj apparently threatened to shoot her.

The singer arrived for American Idol auditions in Baton Rouge, Louisiana on Friday with a police escort, several bodyguards and minders in tow.

The 42-year-old, who is a new judge on the panel alongside the rapper, country singer Keith Urban and veteran Randy Jackson, lived up to her diva reputation as she strutted in for her day on set in Baton Rouge.

One burly bodyguard helped her keep her balance by holding onto her arm while another had the rather important task of shielding her from the sun with an umbrella.

She appeared rather uptight over the recent feud, constantly looking over her shoulder with a worried expression on her face.

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