BLADE RUNNER star, troubled ex-starlet, SEAN YOUNG arrested at Oscars post party.

According to reports, Sean got into a screaming match with a security guard and then enraged, reportedly slapped him.

LAPD 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.

Young was processed at a Tinsel Town police station and released at 2:55 am PT Monday, according to City News Service.

Young — who appeared on Celebrity Rehab last year — has a history of past incidents at swanky Hollywood functions.

In 2006, she was booted from the Vanity Fair Oscar party, and two years later, she was ejected from the Directors Guild of America awards, reported.

In 1988, actor James Woods sued for $2 million, accusing Young of stalking him after they appeared together in the movie The Boost.