Beyonce slapped by fan, reacts fiercely

Beyonce's alter ego, Sasha Fierce, jolted out of her this weekend when she received some unwelcomed touching from a fan.

As she performed Monday at the Forum Copenhagen in Copenhagen, Denmark, the 31-year-old singer was slapped on the derriere by a male fan, which evoked a fiery reaction from her.

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"I will have you escorted out right now, alright?" Beyonce responded after the man spanked her.

The incident occurred while she was playfully interacting with fans in the front row as she performed her No. 1 single "Irreplaceable." The fan then overstepped the boundaries and slapped her on the behind as she walked away.

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As you can see for yourself in the video, the wife of rapper Jay-Z and mother of their 17-month-old daughter Blue Ivy wasn't too keen on the boundary-crossing slap.

Beyonce was performing in Denmark as part of the European leg of her Mrs. Carter Show World Tour.

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The "Run the World" singer will perform in Europe for the rest of the week before taking most of June off prior to her North American leg, which will commence in Los Angeles on June 28.