Vigilance-led anti-smuggling investigations must be handled by the Central Intelligence Unit, otherwise by the Special Intelligence unit. Anti-smuggling matters presenting a vigilance angle must be investigated by the Central Intelligence Unit (CIU), while matters that involve only revenue loss or prohibition/restriction violations without a vigilance aspect are to be handled by the Special Intelligence and Investigation Unit (SIIB). Cases discovered to fall within the other unit's remit after initial assessment must be transferred accordingly. Custom Houses are advised to establish CIUs, place them under senior Commissioner-level oversight, maintain registers and periodic reports, and ensure liaison with other enforcement agencies.