A U.S. army private has testified about the stress of combat at a military hearing looking into allegations that four American soldiers raped and killed a 14-year-old Iraqi girl.

Private First Class Justin Cross told a U.S. military court in Baghdad Tuesday that frequent deadly attacks by insurgents raised combat stress. He said constant fear depressed his platoon in the dangerous Mahmoudiya area south of Baghdad where the alleged rape and killing took place in March.

The court heard graphic testimony Monday of how three soldiers raped and killed the teenager while another soldier killed three family members. The girl's body was later set on fire.

U.S. military officials are trying to determine if there is enough evidence to begin a court martial against the soldiers.

The four soldiers could face the death penalty if convicted in a court martial.

A civilian court in the United States is set to try a fifth suspect, Steven Green, for his role in the alleged attack.

He is discharged from the army.
Iraqi Prime Minister Nouri al-Maliki has called for an independent inquiry into the incident.

Some information for this report was provided by AFP, AP and Reuters.