An officer responded to the platform regarding a male suspect threatening a BART employee, brandishing a knife and pounding on a terminal zone window with his hands. The officer managed to safely detain the suspect as an assisting officer and sergeant responded as well. Further investigation determined that the suspect, who was upset after claiming to have left personal property aboard a train, threatened to batter a train operator while also brandishing a knife. During this time, a second BART employee approached the terminal zone office and the suspect threatened this employee as well, while also brandishing the knife and then battering the (second) employee with a backpack. The suspect was placed under arrest for criminal threats, brandishing a weapon, battery and issued a BART prohibition order. He was then booked into the county jail. The BART employees were not injured during this incident. Platform video was requested, and the sergeant performed a use of force investigation.