The emergency services will practise their response to a major incident during the London 2012 Games when a large scale exercise is staged this week.

Lessons learned from the July 2005 bombings will feed in to the two-day live exercise - dubbed Forward Defensive - in central London.

The disused Aldwych underground station, near London’s Royal Courts of Justice, will be the scene of a mock incident on the tube network on 22 February. Passers-by will be able to spot people being evacuated as part of the mid-morning test.

Other less visible security work will be carried out through to the following day.

The two-day event will be staged as if it is 8-9 August this year, which will be two busy days in London during the Games.

It will involve everyone from “constable to Cobra,” the top level government committee which sits during national emergencies and times of crisis, the National Olympic Security Coordinator, assistant commissioner Chris Allison said.

Emergency responses dealing with casualties and the crime scenes will be tested along the co-ordination and communication systems across a range of organisations that have been brought together for the Games.

It will be a chance to see how decision-making on the ground works in relation to the complex command and security planning which has been worked out on paper and in mock table-top exercises.

Mr Allison said: “This is part of a national exercise.

“The majority of stuff that the public will see, because clearly they will not be underground, will be the people coming out of the Tube system afterwards.

“It is for us testing our first responders capabilities and what we have learned to make sure that we have got that in place from 7/7 (the 7 July 2005 bombings).

“Then there is the follow-up across all these commands and communications nodes who normally do not work together.

“Here we are doing it in a live exercise. It is testing communications right from the very bottom from the constable or fire officer who is responding right the way up to Cobra.”