Security at Wimbledon has been stepped up amid fears that the venue is vulnerable to a car bomb attack.

Contingency plans have been revised following a review last week and in light of intelligence that extremists might adopt tactics used by insurgents in Iraq.

The home of the All England Club is seen as particularly vulnerable to a ‘vehicle borne bomb’ because it is ringed by public roads.

Unlike other high profile targets such as the House of Commons and the new Wembley Stadium, it is very difficult to block off nearby highways with concrete barriers because they are needed by residents.

The police refused to reveal specific measures but they are likely to include random spot checks on trucks and vans. This tactic has already been adopted in London after Sir Ian Blair, the Metropolitan Police Commissioner, described ‘vehicle borne weaponry’ as the ‘greatest danger we can face’.

Other changes to arrangements at Wimbledon include “airport-style scanning” and “sterile areas” as well as more vigilant staff vetting.