A verbal confrontation ensued between a man and male juvenile while on the platform. The man then threatened to shoot the juvenile, and reached into his backpack for an object that was in a holster. The object turned out to be a can of mace, but the suspect did not brandish it. The juvenile positively identified the man who was placed under arrest for making threats to a patron. The suspect was also issued a 30 day BART prohibition order. A warrant check on the juvenile revealed an outstanding no-bail arrest warrant out of Alameda County for escaping from a juvenile detention facility. The juvenile was placed under arrest for the warrant. A sergeant was on scene to approve the arrests and debrief the suspects.