After the devices were removed, the Boston Police Department stated in its defense that the ad devices shared "some characteristics with improvised explosive devices", which they said included an "identifiable power source, a circuit board with exposed wiring, and electrical tape". Investigators were not mollified by the discovery that the devices were not explosive in nature, stating they still intended to determine "if this event was a hoax or something else entirely". Although city prosecutors eventually concluded there was no ill intent involved in the placing of the ads, the city continues to refer to the event as a "bomb hoax" (implying intent) rather than a "bomb scare".