Don't panic: scheduled terror event

Pedestrians around Aldwych in central London on Wednesday morning need not be alarmed by squadrons of police and ambulances and the sight of commuters being evacuated from the Tube.

About 2,500 people are taking part in "Operation Forward Defensive", a large-scale Olympics counter-terrorism training exercise, the "most complex" that has been attempted to date, according to Chris Allison, the Metropolitan Police Assistant Commissioner for the Olympic and Paralympic Games. Local Police Gold Command Centres at the Olympic Park and at other venues such as the sailing centre in Weymouth will also be involved.

The exercise will be set as if it were 8 August and will test the response to a "terrorist incident" on the Underground network, and will occur at a disused station in Surrey Street, Aldwych.