Where are the July 21 bombers?

* IN HIDING?

Several of the bombers expected to die in the attacks and will not have made an escape plan. Police believe they have the names of all suspects and are tracking friends and associates who may be hiding them, most likely in London and the South-east. They will also be listening to telephone calls. One theory is that, having failed in their mission, the bombers may have taken their own lives.

* PREPARING FOR ANOTHER ATTACK?

Police fear two of the men thought to be suicide bombers are desperate and could attempt another attack in London, although they could struggle to locate new bombs, or explosives that work.

* REGROUPING?

It looks increasingly likely there is a link between the suicide attacks on 7 July and the failed bombers of 21 July. It means there are likely to be several planners or leaders still in the UK. Police fear those "masterminds" could activate further terrorist cells or help the four fugitives.

* ABROAD?

All ports were alerted within hours of the attempting bombings. By 3am on Friday 22 July police had photographs of the four suspects and at least two of their names, which were sent to port authorities. The chances of the suspects escaping abroad is said to be very slim.