Emergency exercises will take place in Newcastle

The event has been organised by the Health Protection Agency while the city council will co-ordinate the emergency services and hospitals.

More than 200 volunteers from cadet forces will pretend to be casualties of a chemical or biological leak.

The results of the day will be passed on to authorities across the country.

The event will take place at the Civic Centre on 28 April, and Northumbria Police will secure the area and six ambulances will be on hand to deal with the pretend patients.

'No specific threat'

The exercise will test the effectiveness of decontamination equipment and the ability of the health service to deal with large numbers of casualties.

It will also look at the effectiveness of call-out systems for major incidents and arrangements to prevent damage to the environment.

Dr Nigel Lightfoot, director of the emergency response division at the Health Protection Agency, said: "There is no specific terrorist threat to Newcastle, but attacks could potentially happen anywhere and we need to make sure that we are prepared for every possibility.

"The selection of Newcastle is part of an ongoing programme of health-related civil contingency exercises.

"Training exercises are an important part of ensuring emergency services are well prepared for major incidents, including those caused by terrorist attacks.

"Only a relatively small area of Newcastle city centre will be affected and we aim to keep disruption to everyday life and local health services to an absolute minimum."