Hundreds of paramedics, firefighters and police are taking part in a simulation in the port of Dover.
Crews will be cleaning up a simulated chemical spill from a lorry which has accidentally dropped its hazardous cargo.
Officers are keen to stress that this is an exercise so residents should not be alarmed if they hear sirens in the area.
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Simon has Saturday's forecast for the west of the region
Simon has Saturday's forecast for the east of the region
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