A soldier with the storied 101st Airborne division was sentenced to 18 years in jail after he pled guilty to his role in the killing of three Iraqi detainees during a raid north of Baghdad, the military said.

Private first class Corey Clagett, 22, was the third soldier to plead guilty in the May 9 incident in which soldiers cut the plastic cuffs binding the detainees to make it look as though they were shot trying to escape.

They then threatened to kill a fellow soldier if he reported what happened.

The investigation of the four men from the famed Kentucky-based "Rakkasans" -- the 3rd Combat Brigade of the 101st Airborne Division -- focused a critical light on the US military's controversial and opaque rules of engagement in Iraq.

The soldiers said they were ordered to "kill all military-aged males" in the assault on a suspected insurgent base on an island in the Tigris river.

Some of the witnesses who confirmed they had heard that order from Colonel Michael Steele testified at a military hearing last year that this did not apply to suspects who were clearly surrendering.

The unit's motto, which is emblazoned in front of brigade headquarters in Tikrit, the hometown of executed former president Saddam Hussein, is: "We give the enemy the maximum opportunity to die for his country."

A witness at the hearing confirmed that the unit kept a board recording a "kill count," but that it had been taken down because it was felt to be in "bad taste" after it was used to record the death of a pregnant woman shot at a roadblock.

Clagett pled guilty to attempted premeditated murder, conspiracy to commit premeditated murder, premeditated murder, conspiracy to obstruct justice and obstruction of justice.

Staff Sergeant Raymond Girouard is scheduled to face court martial March 5.

Specialist William Hunsaker was sentenced to 18 years in jail after pleading guilty earlier this month to attempted premeditated murder, conspiracy to commit premeditated murder, premeditated murder, conspiracy to obstruct justice and obstruction of justice.

Specialist Justin Graber pled guilty to aggravated assault with a dangerous weapon and was sentenced to nine months in jail.