Mock earthquake test for rescue teams in Portsmouth
About 500 rescue workers from seven countries have gathered in Hampshire for a two-day disaster exercise to test how they would react to an earthquake.
Exercise Orion has been hosted by Hampshire Fire and Rescue Service near Fort Widley in Portsmouth.
Mock scenarios, such as a badly damaged motorways and collapsed apartment blocks, have been created.
It is designed to test emergency teams "to the limit" by dealing with an incident unlikely to happen in the UK.Hundreds of casualties
Pete Crook, of Hampshire Fire and Rescue Service, said it "was about exercising the unthinkable".
He said one of the main aims was to test the activation and understanding of the EU's various emergency teams in providing help for an affected member state if it faced such a disaster.
The teams have worked at the various sites created around the fort to assess how they would deal the challenges.
The fictitious earthquake has caused apartment blocks to collapse
They are told that a medium scale earthquake has hit Hampshire resulting in 600 casualties in the fictitious town of "Widley".
It has caused motorways and apartment blocks to collapse and has damaged an oil storage plant.
However, British emergency services will soon be overwhelmed and the Cabinet Office issues an appeal for European Union assistance.
Teams from Denmark, Germany, Italy, Norway, Spain and Sweden have taken part along with an urban search-and-rescue team from the United Arab Emirates.
Mr Crook said: "Exercise Orion is deliberately being organised to challenge all teams to the limit.'Unlikely scenario'
"That is why we have chosen the unlikely scenario of an earthquake, because the UK is not accustomed to such incidents and it is therefore outside all normal planning assumptions.
"Some of the participants will have experienced first hand the devastation caused by an earthquake having responded to Haiti or Indonesia last year and seen how easy it is for local emergency services to become overwhelmed by the sheer scale of the situation they face."
Hampshire Constabulary, South Central Ambulance Service, BASICS Hampshire, Fareham Borough Council, the Environment Agency and Hampshire County Council all took part in the exercise.
The exercise is being funded through a 1m euro European Union grant.
A similar exercise is being carried out on Merseyside, testing emergency service teams from across England and Wales, who are dealing with a mock-collapse of the Birkenhead Tunnel.
Market Rasen in Lincolnshire was hit by the biggest earthquake in the UK for nearly 25 years in 2008. It caused damage to chimneys and roofs.