A security dye pack disguised as a bundle of currency for deterring robberies includes a housing formed from a stack of currency bills sewn together and having a hallow chamber formed therein. A substrate disposed within the chamber has a flexible central region through which electrical conductors extend for making electrical interconnections between opposing ends of the substrate. Electrical components are mounted on both sides of the flexible central region to generate an actuating signal upon detecting removal of the security dye pack from the protected premises. Canisters containing dye or other active chemicals are secured at opposing ends of the substrate to emit dyed or other active chemicals in opposing directions when expended. The flexible central region of the substrate allows the security dye pack to be bent into a U-shape. Batteries are arranged in a side-by-side relationship in an elongated narrow case to facilitate bending of the security dye pack.