The Department of Finance is seeking a contractor to build and manage a radio network to carry both voice and data services for the Garda, fire and ambulance services and other "non-commercial bodies in the Irish public service, " such as the Office Of Public Works.

The deadline for applications passed on Friday. Eircom, BT Ireland and O2 all lodged bids while industry sources said several other groups including Nokia and former NTL subsidiary Arqiva were preparing bids but could not confirm whether they had submitted their applications.

Eircom is heading up a consortium which includes mobile telecoms equipment manufacturer Motorola and network specialist Sigma Wireless.

Motorola also has a foot in the O2 Ireland camp alongside Airwave, O2's Britishbased subsidiary. Airwave runs the largest digital radio system in the world which is used by the police and ambulance services in Britain.

BT Ireland is working with EADS, a division of aircraft manufacturer Airbus, and Siemens. EADS recently built out a pilot digital radio network for the Garda, which was trialling a digital radio technology known as Tetra (Terrestrial Trunked Radio).

Estimates produced by the Garda at the time of the trial put the cost of rolling out such a network on a nationwide scale at about 100m.

Industry sources suggest that a comprehensive digital radio network to cover all the emergency services and the other bodies included in the tender would cost substantially more than this.

Building a secure digital network is a priority for the Garda in particular. The analogue radios currently issued to Gardai are vulnerable to third parties seeking to jam signals or intercept calls between Gardai using scanning equipment.

The Department has stipulated that the network must operate nationwide and up to a range of 12km from the coast. It must be also be compatible with radio networks used by the emergency services in Northern Ireland.

The Department will shortlist up to five bidders in March and seek further information before announcing a preferred bidder in June.