Britney Spears Walks Off 'X-Factor' Set -- Again!

They might have to hold this one against her.

"X-Factor" judge Britney Spears walked off the show's set during auditions Friday afternoon -- just one day after TMZ reported she stormed off "angrily" following a hopeful contestant's cover of one of her hits. (The singer, 30, slammed the report via Twitter later that day. "Britney walks off??? LOL was just taking a little break people," she wrote. "I am having the BEST time!!!")

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"After a very popular contestant finished, Brit stood up and immediately walked towards the tunnel where judges enter," a show source tells Us Weekly of the pop star's dramatic exit Friday afternoon -- adding that it wasn't clear what spurred the departure. "Her bodyguards [and entourage] jumped up and ran after her. She was moving fast ... It was odd." (The witness adds that, after a little while, "she came back," as though nothing unusual had happened.)

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During Thursday's auditions, the "X-Factor" source told Us that Spears -- who will reportedly see a $15 million payday for her stint on the show -- seemed "uptight" compared to her fellow judges Simon Cowell, LA Reid and Demi Lovato. "Her body language was reserved," the source shared.

"Demi, Simon and LA," on the other hand, "seemed very relaxed and engaged with contestants and the audience," the witness recounted.

This article originally appeared on Usmagazine.com: Britney Spears Walks Off X-Factor Set--Again!

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