LONDON • In the heart of London, three masked men armed with assault rifles descend on a Tube station, firing at civilians.
So began Britain's biggest-ever counter-terror exercise. Around 1,000 police officers, special forces, ambulance and fire crews took over the disused Aldwych station in the West End theatre district on Tuesday for the drill, dubbed "Strong Tower".
The aim was to "make sure that should the worst happen, we are ready. And we will be", said Metropolitan Police Commissioner Bernard Hogan-Howe.
Only a handful of officials at London police headquarters in Scotland Yard were told in advance about what was to unfold in order to make the mock terror attack as realistic as possible.
The two-day drill had been six months in the planning and officials stressed it had no link to last Friday's bloody attack in the Tunisian resort of Sousse which killed 38 people, among them an estimated 30 Britons.
"Strong Tower" draws on terror attacks such as that on the Charlie Hebdo magazine offices in Paris in January, the hostage-taking at a Sydney cafe in December and the Mumbai attacks of 2008.
Would we be ready if there was that style of attack, whether it be France or Tunisia or wherever it may be, would we be ready for that style of attack here in London?
DEPUTY ASSISTANT COMMISSIONER MAXINE DE BRUNNER
Deputy Assistant Commissioner Maxine de Brunner said the force was testing a "marauding terrorist attack". Describing the scene, she said: "We've seen three terrorists start to open fire on the street just below us and then go into the Tube station carrying on firing their weapons, eventually culminating in some hostages being taken onto the Tube."
The exercise comes ahead of the 10th anniversary of the July 7, 2005 attacks on London's transport system, when four suicide bombers killed 52 people.
"We have looked at events across and around the world since 7/7 and have said to ourselves, 'Would we be ready if there was that style of attack, whether it be France or Tunisia or wherever it may be, would we be ready for that style of attack here in London?' " she said.
Officials said much of the exercise would be held out of public view, but warned that passers-by might hear loud noises and see streets cordoned off.