Recruitment agencies have played a vital role in dealing with police shortages in the aftermath of the 7 July terror attacks by parachuting in recently retired, but highly skilled officers.

The attacks showed how forces rely on seconding in experienced officers from other regions to help in emergencies or solve large cases.

But the Metropolitan Police’s appeal for help meant other regional police forces had to donate some of their best officers, leaving other cases unsolved.

The temporary officers took up the investigations and other policing work to prevent casework piling up.

Police officers typically retire after 30 years, and a massive recruitment drive in the mid-1970s means there are 20,000 officers who have retired in the last five years.

RIG Police Recruit has more than 200 contractors active in a variety of roles including training, investigation work and gathering evidence.

Domenic Bennett, managing director of RIG Police Recruit said: “Temporary staffing is becoming more and more accepted. Forces have been able to achieve their targets and performance figures have improved as a result.”

The temporary officers use their skills in a wide range of projects, including investigations, evidence gathering and interviewing.

A recent recruitment campaign by the government to find the next generation of police officers has left meant the force has a need for high-quality training.

Recently retired officers are also transferring their experience to the new wave of police recruits through training programmes.

Keith Rogers, former chief superintendent of Surrey Police, told Recruiter: “Retired police officers provide a pool of skills and experience that is readily available. Temporary staffing will always be an element of the police force.”