EMERGENCY services from across the North-East and North Yorkshire staged a terror attack in the heart of the region yesterday - to test their response.

More than 200 people descended on a Teesside port as police, fire and ambulance crews, played out a terrifying scenario in which two people were killed by the biological agent ricin.

The day started before 6am when specialist police officers from areas including Humberside and South Yorkshire were mobilised after Teesport, on the outskirts of Middlesbrough, reported an explosion on a ship.

The police's chemical, biological, radiological and nuclear (CBRN) specialist teams travelled in convoy to the scene of the incident where they discovered two people were dead, and more were walking wounded.

Cleveland Fire Brigade and Tees East and North Yorkshire Ambulance Service (Tenyas) also attended the scene, where it set up decontamination tents in the field.

Bill Johnston, senior emergency planning officer for Tenyas, said: "Contaminated casualties would be stripped of their clothing, rinsed and then decontaminated, before being transferred to hospital. It was a very worthwhile exercise."

The fire brigade is responsible for decontamination if large groups are involved.

Graham Dennis, of Cleveland Fire Brigade, said: "Up to ten people can be decontaminated every three minutes."

Since terrorists destroyed the twin towers in New York on September 11, 2001, emergency services in Britain have set about planning and practising ways of dealing with an attack, as well as trying to reduce the risks of an attack.

Two years ago, Northumbria Police staged a mock chemical attack at the Civic Centre, in Newcastle. But yesterday's event was the first time a scenario on this scale has been hosted by Cleveland Police.

The exercise was designed to ensure that the police forces from Northumbria down to Humberside were able to work efficiently together in the event of such an incident.

Inspector Cameron Mann, of Northumbria Police's operations department, said: "The problem with having 43 police forces in the country is that there are usually 43 different ways of doing the same thing.

"We have been working hard to identify the best ways of responding to a CBRN incident and then we all respond together in that way."

Ideas born in the North-East have already been developed into national best practice.

Insp Mann said: "The North-East is well ahead of other parts of the country in training together regularly and testing plans for this type of attack."

Chief Inspector Clive Pengilley, of Cleveland Police said: "There has never been a CPRN incident in this country, but we need to practise our skills.

"In the North-East, we know that as a region we can respond.

"That is what an exercise like this is about. It shows that we can work with other forces emergency services."