By Jen Heger - Breaking Celebrity News Legal Editor

Celebrity Rehab alum Sean Young, who was arrested Sunday night in Los Angeles after allegedly slapping a security guard at the Governor's Ball after the Academy Awards, has fallen off the wagon, and is drinking alcohol again, Breaking Celebrity News is exclusively reporting.

As we previously reported the star of Ace Ventura: Pet Detective, according to reports, got into a heated tiff with security guard and slapped him.

Police said Young, 52, was taken into custody at 9:25 pm PT Sunday at the Governor's Ball in connection with investigation of misdemeanor battery. She bailed out of jail around 3 am PT.

VIDEO: Sean Young Booted Off Skating With The Stars

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