Reality star Paris Hilton's new model boyfriend River Viiperi has been arrested in Las Vegas on suspicion of battery.

The famous socialite and her beau were partying at XS nightclub at the Encore hotel in the early hours of Monday morning when the 21 year old reportedly punched a fellow reveler during an altercation.

Viiperi was taken into custody, cited for misdemeanor battery, and later released.
 
According to TMZ.com, the incident is currently under investigation, and the alleged victim, who was forced to seek medical treatment for his injuries, is planning to press charges.

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