United States military prosecutors are demanding the death penalty for an American soldier accused of killing 16 civilians - nine of them children - in southern Afghanistan.
The killings in March prompted a backlash by the Taleban, and by Afghan soldiers working with NATO troops.
Several soldiers told the preliminary hearing that Sergeant Robert Bales returned to their base covered in blood, the BBC reports.
Sergeant Bales' lawyer says there is not enough evidence for him to stand trial.
The lead investigator, Colonel Lee Deneke, will make his recommendation to a senior general by the end of this week, who will then make a decision on whether the court martial should go ahead.
Military prosecutor Major Rob Steele told the hearing in Washington state said the death penalty should be considered due to the "heinous, brutal and methodical" nature of the crimes.
Sergeant Bales faces 16 counts of murder, six counts of attempted murder, as well as charges of assault and using drugs and alcohol while deployed.
The hearing held evening sessions to ensure victims and relatives of those killed in the two villages in Kandahar province could testify via video link.