A passenger called to report a male on the train who appeared to be engaged in narcotics activity and also masturbating. Officers intercepted the train at the station and located the suspect. He was found to be on probation with a condition of probation to stay away from BART. He was taken into custody for the violation and also found to be in possession of a small amount of methamphetamine. He was booked into the Glenn Dyer Jail for the court order violation and the possession charge.