Nicole was driving the wrong way on the freeway?!

TMZ has learned that Nicole Richie was arrested for DUI early Monday morning. She was booked at 4:50 AM today and was released around 7:15 this morning. The booking sheet reveals Richie is 5'1" and 85 lbs.

We're told two motorists spotted her SUV going the wrong way on the 134 Freeway in Burbank. The drivers called 911.

When the CHP responded, Richie was stopped in the carpool lane and was alone in the vehicle. When cops approached the vehicle, Richie was on her cellphone.

Law enforcement officers tell TMZ Nicole Richie admitted she had taken Vicodin and smoked pot.

This is not the first brush Richie has had with substance abuse. In 2003, she pled guilty to heroin possession. The charges were dismissed after she completed the terms of her probation.

The CHP just informed TMZ the department will not release Richie's mugshot.

I'm not sure which is scarier... Nicole driving in the wrong direction on the freeway, or Nicole weighing in at 85 pounds. When you weigh that little, do you even count as a person? I would have thought that when they pulled her SUV over, they'd be shocked to find that no one was even in the vehicle. Just something that seemed to be a french fry with a wig on.

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