<span lang="en">Emergency telecommunication systems play an important role in people's daily life, supporting communication for the public and first responders during emergency related incidents. Nonetheless, the majority of existing emergency communications are limited to traditional voice and text message services due to the data bandwidth constraint of current networks. It is well known that emerging 4G broadband communication technologies have the ability to provide a range of multimedia services (e.g. picture transmission) that could be utilised by the emergency services to save lives. However, a secured emergency conversation cannot be established between incompatible mobile/end devices without the assistance of a security gateway. Therefore, this paper proposes a technology independent security gateway that provides security support for future emergency telecommunication systems. The proposed security gateway works in three modes to cover all the situations in which its assistance is required to establish a secured emergency conversation. In addition, the development process of the security gateway will also be fully discussed in this paper.</span>