Dubai police have released photographs of an explosive device that US authorities say originated in Yemen and was bound for Jewish sites in Chicago.

The device appears to be an older-model Hewlett Packard printer placed in a standard brown, cardboard box filled with innocuous books and clothing. The ink cartridge inside the printer is stuffed with a white powder and connected to a circuitboard by wires.

US Congresswoman Jane Harman, a Democrat from California, told the New York Times newspaper that the powder is pentaerythritol tetranitrate (PETN), the same material that 23-year-old Nigerian Umar Farouk Abdulmutallab stowed in his underwear and attempted to ignite while on a passenger jet above the United States on December 25.