By Andrew North
BBC News, Baghdad
Thousands of recruits are being trained by the US army for Iraq's new police force - but with insurgent attacks, increased sectarianism and "on the job" training, the challenges are enormous.
"Loud, you've always got to shout loud," barks the instructor, holding a mock pistol.
The morning lesson at the Baghdad police academy is about how to stop and search a vehicle.
"Stop, don't move!" the instructor bellows at two recruits inside the police land-cruiser serving as the suspect car.
"Any vehicle you stop, expect violence," Sergeant Rafid Rahim tells the other recruits watching nearby.
It is week six of their 10-week basic training course.
"Stay well back until you have everyone under control," he advises.
"Drop your keys out of the window!" he shouts again.
On average, 120 police officers are killed every month in bombings and shootings
It may be an exercise, but his tone brooks no discussion. The keys come flying out, before the instructor orders out both men and forces them to kneel on the ground, hands on their heads.
It is the kind of no-nonsense, focused training you would expect to prepare these recruits for one of the most dangerous beats in the world.
Iraq's emerging new security forces have become the main target of insurgent attacks.
On average, 120 police officers are killed every month in bombings and shootings - three or four times higher than current US casualties.
'Year of the police'
It is on this fledgling police force and its performance that US hopes of beginning to withdraw significant numbers of troops depend.
There has been progress and yet there are still real doubts about how prepared this force is, and concerns that many units are more loyal to Shia militias than to the central government.
That is why the Americans are pumping hundreds of millions of dollars into an expanded training programme.
The Baghdad police academy is the biggest of eight such centres, which produce 3,000 new police officers a month.
The US is investing millions of dollars in the trainee programme
"This is the year of the police," says US Maj Gen Joseph Peterson, who oversees the programme.
Despite the violence they face, including frequent suicide attacks on the training centres, basic salaries of US$300 a month - far higher than the average - ensure a steady flow of new volunteers.
Gen Peterson told the BBC: "We now have 130,000 police trained and equipped", towards a target of 230,000.
In Baghdad, he says, police are already responsible for security in about 40% of the city - although still with the support of Iraqi and US army units.
But they have to increase the training programme massively.
The original plan was for about 80,000 officers.
Those involved in the programme say far they realised more police would be needed to restore law and order.
But with such large numbers now being pushed through training, the question many ask is whether these new police are up to the job.
Once these recruits have finished their course, most are quickly deployed to stations around the country.
They are still considered to be trainees, learning on the job under more experienced officers.
But instructor Rafid Rahim is concerned.
For the unique dangers they will face, he says, they are not getting enough preparation.
"That's why you're seeing so many casualties among the police. Their equipment is not good enough either, against the terrorists in the streets, who have a lot of weapons."
Complaints about equipment is something you hear from many police.
Even in Baghdad, you often come across policemen without bullet-proof plates in their flak vests.
Gen Peterson admits there was previously emphasis on quantity, but insists "we are focused now on professional development".
There is another concern - which has become even more pressing after the upsurge in sectarian strife in the past six weeks - that large parts of the new police force are in effect under the control of Shia militias.
An attractive salary means there is no shortage of volunteers
Reports of 'death squads' wearing police or other official uniforms have become more and more common, particularly in Baghdad.
The interior ministry, which is responsible for the police, is run by members of the leading Shia party - the Supreme Council for the Islamic Revolution in Iraq, which has its own militia, the Badr Brigades.
Particular concern focuses around the paramilitary-style Public Order Brigades.
Gen Peterson admits it is a problem and one they are trying to correct.
"As we stood up those forces, we never asked 'Are you a Shia or a Sunni?'," he explains.
But last year, he says they realised they were "predominantly Shia".
He said he went to the interior minister and told him: "Your public order division does not reflect Iraq and I'm asking you not to allow more Shias in and to allow in others - so we can get a balance of forces."
He says the minister agreed.
But there are real doubts as to whether things are changing.
One Iraqi official involved in police training, who asked to remain anonymous, told the BBC the interior ministry was still trying to prevent other groups from entering the force.
"They have the lists of people who apply, and they decide who can go to the academies," he said.
It was something several police at the academy confirmed - almost everyone here is a Shia, said one.