The deputy police chief for the capital had wandered in to an interview by The Times with a senior officer who had once been a poster boy in the post-war recruitment drive and who was now trying to quit in despair at the plight of the police force.

Morose but friendly, the brigadier complained that, as the first security force to be re-established after the invasion, his beat police were thrown into the fight against anti-American guerrillas and terrorists, for which they were untrained and ill-equipped.

Brigadier al-Nayef told The Times: “When they attacked al-Amel police station (the police headquarters in southern Baghdad) and killed 14 officers, one of the policemen who survived said he heard the terrorist say to the man whom he was about to behead: ‘This is revenge for one of our guys who was captured’. ”

It was a mistake, the brigadier said, to have ordinary community policemen taking on the most deadly terror groups in the world. “I lost many good friends when they bombed this station,” he lamented.

Yesterday morning he and his son, Khalid, a police lieutenant, set out from their home in the dangerous southern district of al-Doura for the police headquarters across town. A few hours later, photographers were capturing images of their bullet-riddled corpses in the city mortuary.

The killings were the latest in a series of high-profile assassinations by insurgents, who murdered Baghdad’s Governor last week in another well-planned ambush in broad daylight.

Guerrillas have repeatedly targeted Iraq’s poorly equipped police force and army, trying to undermine security and allow crime and terrorism to flourish.

The day before the brigadier was killed, insurgents had shot dead the deputy police chief of Samarra, which lies to the north of Baghdad.

As the brigadier’s body was being ferried to the mortuary yesterday, two more of his officers died when a suicide bomber in a car made to look like a police vehicle blew himself up in an area of southern Baghdad.

Insurgents have killed more than 100 Iraqis in the past week alone, mostly members of the security force whom they regard as collaborators with foreign occupiers. Bloodshed has been especially heavy in the heartland of Saddam Hussein’s once-privileged Sunni minority.

Several powerful roadside bombs in the capital have not only killed US soldiers but also destroyed some of their Bradley fighting vehicles, one of the army’s most advanced pieces of armour, crushing a symbol of US military might.

Military assessments of the threat concluded that insurgents have the ability to use increasingly larger, more powerful bombs on American armoured vehicles that tread Iraq’s perilous highways.

In another daylight attack yesterday, a suicide bomber drove an explosives-packed vehicle resembling those used by police into a police compound in southern Baghdad, killing at least three people. Police officers were among the dead and injured.

The Army of Ansar al-Sunna group claimed responsibility for the attack, saying that it had aimed to hurt “apostate forces who are the right-hand men of crusader forces in Iraq”.

With three weeks to go before the election, insurgents have increased efforts to cripple the US-backed interim Government and scare away voters. Iraqi leaders say Sunni Muslim-led guerrillas also want to provoke sectarian civil war.

Iyad Allawi, Iraq’s interim Prime Minister, has insisted that the election will go ahead as scheduled on January 30, but the latest attacks have raised doubts that Iraq’s fledgeling security services can protect voters at the polls, even with the backing of US forces.

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