Photo: Policing the depths of the Tube

The system links the Metropolitan, British Transport and the City of London police forces, as well as the fire and ambulance services.

However, as the fire and ambulance Airwave systems have not yet gone fully live they currently rely on loaned police Airwave radios during incidents.

Here policing minister Vernon Coaker discusses the benefits of the system.

Coaker said: "The benefits are obvious to me, just from hearing officers say that, for the first time, they can connect to other officers or the PNC [Police National Computer] when dealing with a violent or terrorist incident underground."

BTP officers told how tackling violent or unruly travellers on the underground will be much easier with Airwave, as officers can radio fellow officers or the control room for help, as well as send and receive data or access the PNC, the UK police's central database.

Previously, officers had to send a colleague above ground to radio for help, cutting their manpower when tackling often volatile situations.

Photo credit: Nick Heath/silicon.com