An Iraqi court has sentenced an al-Qaeda militant to death for the killing for three American soldiers south of Baghdad in 2006.

Ibrahim al-Qaraghuli was one of three suspects involved in the killings. The others were found not guilty.

The killings were one of the most brazen attacks against US soldiers operating in Iraq.

Meanwhile, there are reports from the northern city of Mosul that four police officers have been killed by gunmen.

The 2006 killings of three soldiers from the 101st Airborne Division took place at an isolated checkpoint near the Euphrates River. At the time the area was known as the "triangle of death".

One soldier was found dead at the checkpoint. The other two were kidnapped and three days later their mutilated bodies were found tied together and booby trapped with roadside bombs.

An al-Qaeda-linked group later posted a video on the internet showing the bodies of the soldiers being dragged behind a truck before being set on fire.

Ibrahim al-Qaraghuli wore a prison jump suit and remained silent as the judge pronounced the death sentence.

The other two suspects Walid al-Kartani and Kazim al-Zubaie - were found not guilty due to lack of evidence, but it was not immediately clear if they were to be released.

Feports from the northern city of Mosul say four police officers have been shot dead.

The officers were among a group of nine policemen who came under fire in civilian cars while travelling to work. Several were wounded.

The attack took place in the Sunni neighbourhood of al-Amil in the west of Mosul, a city which is experiencing continuing violence while the rest of Iraq has seen a big reduction.

Two weeks ago in Mosul, the United States military said it killed the second-in-command of Al-Qaeda in Iraq after a raid on a militants' command centre.