It is the $120-a-month job that is crucial to any Allied exit strategy from Afghanistan but at the moment a career in the police force is only for the desperate.

American efforts to expand Afghanistan’s security forces are faltering, leaving the largest training centre in the country operating at only 25 per cent capacity.

Recruitment has been low in recent months amid rising Taleban violence and political instability after the unresolved election. Thousands of men are leaving the force every month, with about one police officer in three resigning over the course of a year, The Times learnt. Some have joined the Taleban.

“We simply can’t recruit enough police,” General Khudadad Agha, the officer in charge of training, said. “The salary is low and the job is very dangerous. If someone wants $120 (£72) a month then they join up. But 95 per cent of the new recruits are uneducated, unskilled and they can’t find food. That’s why they join the police.”

Plans are under way for a second round of voting on November 7 after President Karzai admitted that he did not have enough votes to claim an outright victory. The police will be in charge of guarding the polling stations, which the Taleban have vowed to attack.

Western mentors admit that bribes are unavoidable, when the cost of supporting a family is double what the men are paid. “The best we can hope for is that, if they are taking bribes, at least they know it’s wrong,” one said.

A strong and competent police force is a central part of General Stanley McChrystal’s counter-insurgency strategy. The top US commander in Afghanistan has called for the force to be increased from about 93,000 to 160,000.

There is still a long way to go. Official figures show that only 1,000 recruits signed up in August. The problem is more severe in Wardak province where, earlier this month, a policeman shot and killed two American soldiers.

Recruits for the Afghan Public Protection Force are usually sent to Laghman to be trained by American Special Forces. “There hasn’t been a single recruit for more than a month and a half,” General Agha said. “More than a hundred people were rounded up and sent to the training centre, but the commander in charge told me they ran away. Iran opened the border [in the west] and they all thought it was better to go abroad.”

Those who do graduate are armed with AK47 assault rifles and most serve as “light infantry in counterinsurgency operations”, according to a critical report by the European Union.

Police officers are more likely to be killed or injured than their counterparts in the Afghan army, who usually serve alongside Nato troops backed up by fighter jets and drones. The police often man checkpoints that are vulnerable to suicide attacks and ambushes.

At least 1,290 policemen were killed last year and 2,393 were wounded; almost 5 per cent of the official total.

Almost 10,000 additional officers were supposed to have been recruited before the election in August. Officials involved in the training process, however, said that most of the men on an emergency three-week course were already serving policemen.

A Western official said: “There weren’t many new recruits, but because they were being trained for the first time it looked like there were more people on the books.”

Western diplomats say that no one knows exactly how many police officers there are, because corrupt commanders claim more salaries than they have staff.

The pre-election police training focused on weapons and included none of the usual lessons in literacy, human rights and law. An independent report said that it was “barely conceivable how eight weeks’, let alone three weeks’, training can adequately bring any form of security”.

The authors added: “Our view is that the spiralling increase in police deaths and wounding will further increase with quick-fix recruiting, poor training and equipping.”

The greatest fear is that graduates will take their training and weapons over to the insurgents. Ahmad Shah, 27, left the police in 2003 and joined the Taleban in Wardak.

“Back then the salary was only $60 a month,” he said. “We were always getting attacked by the Taleban, and I couldn’t visit my family in Jagatur because the Taleban controlled the area. Now I joined the Taleban, I don’t get a regular salary but I get around $300 a month, and it’s much safer.”

Times Recommends

• Please help: maimed children of war want their lives back
• Cabal seizes diamond riches to buy power
• White House gatecrashers got to the president