Emergency crews tackled a worst-case scenario

The experts were taken through the tactics and difficulties of dealing with large-scale casualties in the event of a "dirty bomb" attack by terrorists.

A section of the Majestic Hotel in Harrogate was transformed into a decontamination unit in the aftermath of a dirty bomb being detonated.

The demonstration included fake smoke, sirens, pre-recorded screams and wailing and imitation casualties.

The delegates were shown how the victims would be taken through the decontamination unit, their clothing and jewellery removed, decontaminated and moved on to treatment sections before being taken to hospitals in waiting ambulances.

Chief Superintendent Gavin Edwards, head of planning and logistics at West Yorkshire Police, said: "It was a very frightening scenario and it may well have frightened a lot of people.

"Today's event has been successful as we can see what help and equipment is available."

Richard Bailey, chief executive of co-host Aireshelta, said the event allowed different organisations to share ideas.

"We need people in industry to tell us what they need. We have an idea but today's event allows people to come together and share information and ideas."