That's Pratt-tastic

"The Hills" star Stephanie Pratt (seen here in a mugshot from 2006...) was arrested on suspicion of drunk driving in Hollywood early Sunday morning, the Los Angeles Police Department confirmed.

"It was your basic DUI. Our traffic officers driving down the street spotted her and pulled her over," Sgt. Sal Ogaz told PEOPLE. "She was cooperative and there were no issues with her arrest."

Police records show Pratt, 23, was arrested at 3:45 a.m., charged with a misdemeanor, and was transferred to the Van Nuys jail for booking, where she was released around 10:30 a.m.

Earlier in the evening, Pratt was at fellow cast member Holly Montag's birthday party at Empire, an L.A. nightclub.

At 11 p.m. she Tweeted: "its my sissy @hollymontags bday party! just finished dinner and going to Empire but im pretty tired aka yes i am the party pooper :("

Stephanie, the younger sister of Spencer Pratt, said last month that she'd like to leave the show after 10 episodes. "I don't know how much more I can take of 'The Hills' ... 'The Hills' is very brutal," she said.