Rob Hoffman / DTR / Promotional 1 / 6
Rob Hoffman / DTR / Promotional 1 / 6

Britney Spears sure knows how to drum up excitement for her forthcoming Femme Fatale tour. The popster set off a frenzy on Friday night when she turned up at a shindig hosted by her new opening act, Nicki Minaj, at The Factory in Los Angeles.

An eyewitness says Spears caused "complete pandemonium," so much so that a half a dozen people were reportedly carried out of the surging crowd because they were "hyperventilating" over being in Brit-Brit's presence.

"People were crowd surfing to get to the stage," says the spy. "Screams were so loud for Nicki and Brit you couldn't hear the music. Bouncers couldn't hold the crowd back."

Minaj, who performed earlier in the night with Lil Wayne at the Staples Center, tweeted that the arrival of Britney and fellow guest Khloe Kardashian made it "waaayyy too sexxxy in here right now."

Spears, who hit the party with boyfriend Jason Trawick, returned the compliment.

"I had such an amazing time hanging with Nicki and all the boys at The Factory in West Hollywood," she said. "Nicki is such a star and is so sweet, and you could feel the heat and the energy from the crowd the minute we walked in."

Enthused the promotion-minded superstar, "I think this summer's tour with Nicki is going to be my best ever. I can't wait!"

Britney kicks off her tour with Nicki on June 17 in Sacramento.


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