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Conrad, was arrested and placed on probation in August, 2014 after he pleaded guilty to threatening passengers and flight attendants aboard an international flight travelling from London to Los Angeles.

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He served three years probation and 750 hours of community service. However, Conrad, admitted in court that during his probation he was exposed to using drugs like Marijuana, synthetic cannabinoids and cocaine.

Us Weekly reports that the U.S. Assistant Attorney Alexander Scwab said  Conrad has until Wednesday, June 8, 2016 to surrender to the authority for violating his probation.

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Conrad, who is the heir to Hillton hotel and resort was ordered to undergo mental health treatments and get help through substance abuse programs in the past.