The US-bound package discovered on a plane in Dubai contained explosives and an electrical circuit linked to a mobile phone SIM card, according to police reports.
Dubai police said the bomb, discovered in the ink cartridge of a computer printer in a shipment of air cargo from Yemen bound for the United States, contained the powerful explosive PETN and bore the hallmarks of al-Qaeda.
The plan was bound for a synagogue in Chicago from Yemen. A similar device was discovered on a cargo plane at East Midlands Airport in the UK.
Dubai police have stated they were tipped off by a call from abroad, which warned of the possibility of an explosive device hidden in postal packages on-board the FedEx flight from Yemen.
UK Home Secretary Theresa May has also confirmed the package at East Midlands did contain explosive material, but said it was not yet clear whether it was a "viable explosive device".