Dozens of officers are leaving West Yorkshire Police before they have even served two years, figures have revealed.

Home Office data showed 44 officers who departed in 2006/7 - 13 per cent of total leavers in the 12 months - were relatively new recruits who had not yet completed two years in the job.

The Liberal Democrats, who published the figures, said they showed more needed to be done to keep officers.

Some areas appeared to have even greater difficulties keeping hold of new officers than West Yorkshire.

The worst-affected force was Surrey, where 51 recent recruits made up 27 per cent of departing officers.

The figures included dismissals, resignations, medical and other retirements, transfers and deaths.

The Liberal Democrats said the drop-out rate was due to low morale but chairman of West Yorkshire Police Federation Tom McGhie said changes to training may account for the number.

He said: "Some people join the force and realise it is not for them and some in West Yorkshire leave because they find the foundation degree, which they now go on, is not for everyone. They have blocks where they study the more social science side, go on community placements and write dissertations, as the law is taught at the training centre."

Recruits study at Huddersfield for a foundation degree in police studies as well as spending time at the Force Training School in Wakefield.

Jeremy Browne, Liberal Democrat Home Affairs spokesman, said: "Early drop-out rates reflect low levels of motivation. It is important to retain our expensively-trained police officers.

"Where retention is particularly problematic, there is a risk that the public will receive a diminished service, so this problem must be tackled."

A Home Office spokesman said resignations accounted for 1.5 per cent of the total workforce and had been consistent over the past three years.

And he denied there was low morale in the force saying recruitment and retention of officers was "strong".

He said: "Retention of police officers is good in relation to other occupations - six per cent of leavers for the police compared with between 12 per cent and up to over 20 per cent in other sectors."